Zettelkasten, Roam, Obsidian, RemNote, Notion and Co

Zettelkasten, Roam, Obsidian, RemNote, Notion and Co

I am a professor, based in an institute of computer science. In addition to my regular lectures on data analysis and mathematical modelling, I offer three seminars helping senior students and young scientists with scientific writing, writing grant proposals and a seminar on productivity, time and project management. Taking “smart notes” did not play a role in my seminars, until the renewed interest in the Zettelkasten technique, evergreen notes, and apps like Roam Research, Obsidian, RemNote and Notion created quite a stir in the Internet. I decided to have a go at using those techniques and apps, some of the observations I like to share here.

A short history

The origin of the Zettelkasten technique is usually attributed to Niklas Luhmann, who had a system of small cards (Zettel) and slipboxes (Kasten) to collect notes and link them through a numbering system. He used this system quite successfully to write research papers and books. The key ideas of note taking using the Zettelkasten technique are

  • the notes are short (“atomic notes”), focussing on one idea,
  • rather than just copying things (e.g. from other papers), learning and thinking is supported by formulating the notes in your own words.

Sönke Ahrens published in 2017 the book How to take smart notes, which picked up on the Zettelkasten idea and discussed its value to boost writing, learning and thinking. In a 2020 YouTube video youtu.be/nPOI4f7yCag he describes the history and ideas behind the Zettelkasten technique. Andy Matuschak advanced ideas in Ahrens’ book by introducing the idea of “evergreen notes”. Instead of just having a blog post on the topic, Matuschak presented his idea with a webpage that implements and supports the Zettelkasten technique, using an web-based environment: notes.andymatuschak.org/Evergreen_notes

Evergreen Notes

Matuschak’s Evergreen note webpage includes so called wiki style links, where pieces of text are marked and turned into a link to another note where the title is the marked text. The key is that one not only goes from one note to the other, but can easily navigate back, and is supported in finding other notes that link to the one under consideration. Rather than just implementing the Zettelkasten technique using a web-based tool, Andy Matuschak evolved Luhmann"s Zettelkasten by introducing the process of writing Evergreen Notes as “a fundamental unit of knowledge work”. In order to create notes that are worth developing over time, he stated the following principles:

  • Evergreen notes should be atomic
  • Evergreen notes should be concept-oriented
  • Evergreen notes should be densely linked
  • Prefer associative ontologies to hierarchical taxonomies

There is thus the idea of a writing process, and the tool to support this process. The key elements of Matuschak’s web-based tool, that set off the hype are:

  • When hovering over a linked word or sentence, one can preview that other note.
  • Clicking on the link, opens the other note, together with the previous note. One can view and edit several notes together.
  • The linked note has at the bottom a list of other notes that link to the note.

The preview and “back-linking” supports easy navigation between notes and thereby supports finding links between notes and ideas. The implementation of these ideas were really a fantastic idea, taking the Zettelkasten approach back into a modern setting. Note long after Andy Matuschak’s webpage, the ideas led to the creation of new tools for note taking and learning, most notably roamresearch.com, www.remnote.io and obsidian.md

Back-linking has since been introduced in various other apps, including web-based all-in-one workspace Notion and the calendar-driven notetaking app Noteplan (iOS, Mac). More apps have emerged with support for back-linking, offering new experiences in note-taking. The ones I listed above have probably received most attention.

Other apps, like DevonThink and TheBrain on Mac has long supported the management of large numbers of notes and have also supported finding relationships between notes. The question is what these new new apps add, that the established ones don’t have.


Roam and Remnote are in their initial appearance apps for outlining, very similar to Workflowy and Dynalist. Outlining is an important strategy for researchers who draft manuscripts or their theses. Rather than starting to write down full text, one starts with small units - bullet points, then adds headings and only then fleshes out the text in full text paragraphs. The idea is that bullet point lists make it easier to rearrange things and thinking and writing in bullet points encourages you to be concise.

I do most of my initial outlining by drawing a mindmap, using Mindnode on Mac, iPhone and iPad. The user experience of Mindnode is fantastic, and the fact that one can easily switch between iPhone, iPad and the Mac to edit and visualise the mindmap, makes a difference to quickly view and edit the map/outline. Mindmaps are ideally suited for editing with touch surfaces. In parallel to the actual mindmap, one can also have a conventional outline. I even use mind maps for my seminars, instead of Powerpoint. The one thing that Mindnote is not particularly good at, is the handling of notes attached to elements in the mindmap. The text is just plain text, no formatting, or links possible. All elements of the map are thus things that fit into a single sentence and there is a point when the size of these maps work against the idea of an easy navigation. There is also not the support to connect elements in the map, in the style of backlinks.

Roam, Remnote and Notion also support outlining in an excellent way. It is very easy to collapse and expand lists, and move units of text/lists around. The calendar-based note taking app Noteplan has recently also introduced the collapsing of elements in notes. Noteplan also supports backlinking and thus the Zettelkasten approach. Because Noteplan stores all notes as markdown files on the computer, some users use Noteplan together with Obsidian. Apart from the graph view, I am not sure what the motivation is behind this combination. To summarise the first observation about these new apps, including Roam and RemNote, is this feature:

The ability to collapse and expand lists and paragraphs, and to easily rearrange elements in those notes or lists, are key elements in helping to organise thoughts through outlining.

Support for outlining relies on a WYSIWYG experience, so it does not make sense to outline in markdown directly. Overviewing elements of an outline, to possibly color-code and tag elements and then rearrange things quickly does not work well if you have to switch between the markdown text and its preview, I feel. Apps like Agenda](https://www.agenda.com) and Bear (iOS, Mac) are markdown-based but the writing experience is WYSIWYG, really very well done and user focussed.

On top of my wishlist for Agenda (iOS, Mac) are the collapse and expand feature for elements within notes, and a corkboard view of notes. The backlinking between notes would not be a priority for me in this case.

Note taking

While DevonThink has, in principle, many of the elements that create a hype with other tools. This include links in markdown documents and an ai tool that identifies related notes. The main strength of DevonThink is clearly its ability to handle a vast array of documents, not just notes of a particular type but almost any document. It provides you with databases, that you can also carry around and access from the iPhone and iPad. The reliability and flexibility have not competition in my view. However, when it comes to note taking, the app takes some “getting used to”. I have to admit that I was not really aware of some of these features until I looked at Roam, Obsidian and RemNote. The company also offers a search tool, Devonagent, which I purchased but for some reason I find difficult to describe, I do not really use. The fact that wasn’t aware of some features, despite using the app daily, suggests that there is something with regard to the user experience.

We all know that once people are sufficiently in love with their app, they will adapt to limitations, or find ways to address these for themselves. It does not make sense to then argue with them over usability etc. and I not experienced enough or qualified to judge these issue properly.

Roam and Obsidian have been very clever in creating a user fan base that helps with the development of plugins to overcome limitations and expand the apps to their needs. It would not make sense to argue with them that the many plugins themes and customisation is not only a blessing. I guess, I personally prefer a native Apple app, with a well worked out user interface, so that I do not have to resort to plugins other users have created. It is great if these tools, like DevonThink offer css styling but if an average user tries to figure out how to do that, one can spend easily days and week learning about css styling. The experts in the forums keep saying there is plenty of training material in the Internet … only that this is not user friendly. Ulysses and Obsidian at least offer a gallery of themes that one can easily try out without learning the supposedly simple css. I enjoyed Obsidian and also enjoyed tailoring the appearance to my preferences, only to realise that I spend a lot of time adjusting the tool, rather than using it …

Another key element of Andy Matuschak"s evergreen note webpage was the ease with which to view and edit multiple notes simultaneously. Here Scrivener still stands out with their corkboard. In Scrivener, every section of your project is attached to a virtual index card. Scrivener’s corkboard lets you step back and work with just the synopses you’ve written on the cards—and when you move them, you’re rearranging your manuscript at the same time. Scrivener also supports outlining. Scrivener is targeted at writing long text, similar to Ulysses, and of course Word and Pages. With the corkboard and outlining support, is a major advantage over Ullysses and it puts Scrivener much closer to notetaking apps like Agenda and Noteplan (which set themselves apart with the integration of calendars and reminders). One key idea from the Zettelkasten techniques are atomic notes, i.e. short concise notes. As a result viewing a note, its heading, tags and a few lines of text, does not take much screen estate. This brings me to another observation how note taking can support research:

The ability to display several notes together, side by side and seeing at least parts of the content, is a key element in helping to relate ideas in different notes.

Finding relationships in and between notes

An outstanding feature of Roam, RemNote and Obsidian in particular, is the support the discovery of relationships between concepts and ideas through a visualisation of notes and tags in a graph. While Roam and Remnote are cloud based, Obsidian and Noteplan store all notes as plain text (markdown) files on the computer. In Obsidian one user has taken this a step further and developed a Neo4j plugin that streams the notes in the Obsidian vault into a Neo4j graph databases, thereby providing a serious tool for research.

Turning a collection of notes into a Neo4j graph database, could open up an enormous set of tools to use for the analyses of documents. This is an example how community-driven plugin development pushes new ideas.

TheBrain has long supported a visual approach to organise and link notes. It supports markdown and in its last version also introduces backlinks. While writing notes, the app recognises words that could be linked to other notes and supports the process in a very intuitive way. It terms of visual exploration of notes and linking of ideas, TheBrain is excellent. A challenge TheBrain and Devonthink share is that there iOS versions of the apps are somehow reduced versions of the Mac apps. One reason why note taking and To Do apps like Agenda, Noteplan, and Ulysses are popular, is the fact that using these app on the iPhone, the iPad and on Mac is essentially the same, in terms of the interface and functionality. The complexity and functionally of those Mac apps is probably very difficult to realise on a smartphone.

One thing that clearly sets RemNote apart from all other apps, is the excellent (easy to use and comprehensive implementation) of ANKI style flashcards. Spaced repetition is key concept in learning and something that is very attractive for students.

Task Management

Almost all apps discussed so far, also some task management through to do lists and reminders. I am on of those people that hopes to eventually have only one app, to write notes, manage documents, which can also be used for task and project management. At present, I cannot see how these apps can replace dedicated apps, like ToDoIst (cross platform, including collaboration) or Things for iOS and Mac. The big challenge is here to offer the experience users of iPhones, iPad and Macs are used to. As I write these notes and realise various spelling and grammatical errors, but can’t be bothered to correct them, I am reminded that Ulysses, has a built in language correction tool, which not only corrects spelling and is very useful for non native speakers who do their research in English.


I forgot to discuss Drafts and Craft, and of course there is also Microsoft OneNote, and Evernote. While testing Drafts, I had this amazing experience of using my iWatch to dictate a note. I did not take such fancy feature serious, until I was walking my dog, iPhone at home and it was the easiest thing to just dictate a note that was then on my Mac when I returned home. I never needed this again but I was surprised what is now possible, how easy note taking has become. I keep looking at Drafts but somehow its appearance and principles have not work for me … yet. The search for a perfect most-purposes app will probably never end :slight_smile:

I use DevonThink on a daily basis, but mostly to collect and archive information. It supports note taking with Markdown, it has Wikilinks and it has tools to find relationships between notes. For some reason I do not use these features in the way they are attractive in those other apps. Inspired by the apparent success of Roam and Co, I will try to explore these features more.

I like the ideas that are generated by the Roam and Obsidian communities. Turning a collection of notes into a graph database is only one of those examples. The hype is therefore something we all can benefit from and I found watching Sönke Ahrens talk on YouTube and Andy Matuschak’s Evergreen note webpage inspiring.

Like many of us, I am still on the lookout for changes to my workflows. From my perspective, the key components that define the competition at the moment are:

  • The support for outlining by collapsing and expanding units in notes.
  • The ease of entering and editing links in texts.
  • The preview of notes by hovering over links.
  • The cork-board view of several notes together.
  • The simultaneous side-by side and WYSIWYG markdown editing of notes.
  • The similarity of the experience on iPhone, iPad and on the Mac.

Very interesting, thanks!

I am trying to use DEVONthink for all my document needs, and even if sometimes I am missing features, it is still the best option for me.

This is so, because it allows to encrypt my data locally and on the remote sync location.

About MindNote, I prefer iThoughts, which is technically advanced, IMHO.
Also, it is not subscription-based, which is essential to me.


Thx for this great article.
For most of my coding notes, I use Checkvist. Checkvist is an outliner, keyboard-centric but it can also be used for handling tasks.

To visualize my coding workflow, I use Mindmup.

I add links to these notes inside my tasks that are handled in Clickup.


Very surprised there doesn’t seem to be any mention of https://zettelkasten.de in this. It has been going since 2013 and is the best source of information and discussion on the topic that I have found on the internet. It is also the home of The Archive, which is a development of nvALT, and is purpose-built for making Zettelkasten. There is a very active forum, too. Well worth looking at.


I agree that zettelkasten.de is a great place to become immersed in the slip note theory and practice. I have tried out several of the apps aimed at digital note-taking, including The Archive, but all left me dissatisfied for one reason or another — too cumbersome, too restrictive, too limited in portability, etc.

It occurred to me then that DEVONthink could be an excellent program for this purpose. As usual, others had already thought of this and implemented it. Kourosh Dini has written a book,
“Taking Smart Notes with DEVONthink,” that describes in great detail how he creates and manages notes. I think that a novice could pick up his book, develop an understanding of zettelkasten, and learn how to create a sophisticated implementation of it using DEVONthink. I am not given to hyperbole, but I think his book is astonishingly good!


This is very helpful. Thank you. I also have found a lot of very helpful information at zettelkasten.de.

I’m using Devonthink in tandem with Obsidian and iA Writer at the moment: I find the experience of writing a note in Markdown to be best in iA Writer, but it doesn’t support wikilinks. Writing markdown in Obsidian is very good, and it really scores with wkilinks, backlinks, and the wonderful graph view. My Zettelkasten folder is indexed by DevonThink so I do all my searching there, taking advantage of the amazing AI and the linking with my research files (and also the contents of my bibliographic database, Bookends, and my ebooks in Calibre, which are also indexed).

My big problem at the moment is that I’m still new to Zettelkasten and I’m spending too much time tinkering with the system rather than actually doing the research!


In Söhnke Ahrens’ discussion about the Zettelkasten technique, and looking at the revival of the ideas with Roam, Obsidian, RemNote & Co, there was one aspect that struck a chord with me. It is a key point that I forgot to mention above:

Writing is not the outcome of thinking; Notetaking is the process when thinking takes place.

Thinking does not happen in the brain alone, there is an external dimension to it. Because note taking is thinking, the success of your thinking depends on the way you take notes.

One can use note taking apps to keep or archive ideas but note taking apps can go beyond managing files and support creative thinking and research. I think this is the core of the current wave of interest and the comparison of apps should focus on how apps support this process and most importantly, the ease with which this is possible.

Outlining is a key element in this process, or an example of notetaking as a way of thinking. In research, the process of writing a publication or a long text (e.g. dissertation) is often started with an outline. While many people outline by headings, it is often an good idea to jot down key points of an argument or the results one wants to present, to then start ordering these elements (bullet points, short paragraphs).

Being able to collapse elements in an outline (text below headers, lists etc) and easily move things around, supports this process. Trying Notion and RemNote I immediately found this very useful.

Backlinking is one way to support the discovery of relationships between ideas and concepts, that are stored in separate notes. However, in many instances one has a collection of ideas (bullet points, short paragraphs) in one note, and the process of finding relationships is through rearrangement and ordering of those pieces (inside a note).


We all tend to believe that our own experience is more typical than it actually is (see the False Consensus Effect), so I find myself thinking that Ahrens has perhaps taken this generalisation too far. It does not chime with my own experience, perhaps because I work in a different field, or because I adopt different methods. Or perhaps I just have a different conceptualisation of “note-taking”. I would say that in my own case note-taking is mainly recording things so that I don’t forget them, or can find them again more easily than I would if I had to search an entire library. In my case, the thinking comes when I have to do some writing for an essay, an article, or something of the sort. I use notes more as a repository than as an “idea space”.

I suspect that the current wave of interest in the Zettelkasten method and transclusion is mostly to do with fashion, driven partly by the Availability heuristic. The method is undoubtedly useful to me, but I wonder how many people will take it up and then move on to other things when a new star rises above the horizon. It is not necessarily an easy option, and can involve quite a bit of “gardening” to get full benefit from it.

I have been looking for “the answer” to managing all my research materials for over thirty years, and I have never found it yet. All methods have advantages and disadvantages, and what we make of them is probably more important than what they are in themselves (in my view).

By the way, another element to add to the mix might be Hook.

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It is not necessarily an easy option, and can involve quite a bit of “gardening” to get full benefit from it.

This is the trap I’m falling into at present, after three or four weeks of trying it. One of the things I’ve realised since adopting it is that I have ended up with different tagging/keyword systems in Bookends, DevonThink, Finder, Calibre, etc. They’re not radically different, but all have grown as a function of the way the various bits of software lend themselves to this. So I decided to make all my tags/keywords consistent. It turned out to be a rather more involved process than I expected, but once I’d started it seemed foolish to stop. And then I discover that the tag requirements in Obsidian are different from those in Calibre, etc. :grimacing:

I’m glad to see you recommending Hook. I’m a big fan and find it extremely useful for connecting things within apps when there’s no inbuilt linking system (as in DT3) and especially between things created in different apps. To be able to link a Bookends reference, an ebook in Calibre, a few useful web pages, something I wrote previously, and some items in DevonThink to something I’m working on now is brilliant.

The problems you mention are among the reasons why I use The Archive for my Zettelkasten. I have come to realise that for my purposes, the simpler the solution, the better. In the past I have tried to invent ways of getting to information from several different directions, but I found that merely created friction, uncertainty, and confusion. Now I have my notes as plain text files, with hashtags in the body of the note (sometimes with Finder tags, but not always) and I either search inside The Archive, or I use HoudahSpot (sometimes alongside Alfred actions). And of course Hook is useful for linking things together (I put links in the body of my plain text notes). I can also link to Bookends items by putting the item link in the body of the plain text. It works pretty well. Hashtags in the text have turned out to be surprisingly useful.

I think Ahrens’s point, though, is that a properly managed zettelkasten blurs the line between “research” and “writing.” Rather than writing an essay or article being a separate “thing,” it becomes a matter of assembling pre-existing notes.

I’m in the early stages of my zettelkasten experiments, so I haven’t yet fully embraced that process, but it seems promising.


Thank you @Wolkenhauer for the great post. I’ve looked at many of these tools and have wanted to compare them for some time but haven’t gotten around to organizing my thoughts, which you did quite nicely. :grinning:

I wrote my PhD dissertation using Scrivener (alongside Scapple for thinking through connections and DevonThink for storing primary source material). I found Scrivener to be a fantastic tool for long form writing and organizing notes into a form that is necessarily sequential, linear, and hierarchical. I found that I could easily jot short thoughts into Scrivener before figuring out where they fit, pulling them out into Scapple to find new connections, pulling them back into Scrivener to find a place for them, re-arranging them, slicing them up, re-combining, etc.

I’ve been intrigued by the Zettelkasten technique, by Andy Matuschak’s evergreen notes, and the growing popularity of Roam Research. On the one hand, the non-linear free-associative graph of notes that one can build in these tools is very seductive, and in some ways they better reflect how the human brain works than a hierarchical outliner, for example. On the other hand, I have a feeling that making coherent meaning out of “atomic notes” requires us to order them in some kind of sequential, perhaps hierarchical way. Maybe that is just how my brain works, or just how I’ve been taught to think.

@mbbntu’s point also resonates with me strongly:

I have come to realise that for my purposes, the simpler the solution, the better. In the past I have tried to invent ways of getting to information from several different directions, but I found that merely created friction, uncertainty, and confusion.

These days, I use Workflowy for my note-taking as well as task management. I have used it on and off for perhaps a decade or more and always return to it for its simplicity. When I’ve tried to take notes in DevonThink, I find that all the configuration options lead me to spend more time twiddling knobs, adjusting options, and setting up workflows than actually using the tool. Workflowy is an extremely simple tool that gets out of my way, and they are adding some interesting new bits of functionality that appear to be inspired by some of the newer tools (mirror nodes, kanban boards, fractal boards, bi-directional links). Mirror nodes are a bit like replicants in DevonThink, where a single note can appear in multiple places in the Workflowy outline, but all appearances are really the same note. In some ways, I have found mirror nodes combined with the forced hierarchical representation of notes in an outline to be more useful than free-associative bi-directional wiki links for the reasons mentioned above.

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I have also not managed (yet) to generate through backlinks, or these graphs in Roam and Obsidian something exciting… but as we realise here, simplicity and hence good design for it, is important.

I also found the outlining, which Scrivener, Roam and RemNote implement so well, is something non-fancy and yet useful. For this reason, I think it is good that there is renewed interest in the Zettelkasten technique and it is worth watching that Roam, RemNote and Obsidian space.

I am sure RemNote will be a hit with students - their flashcard implementation is excellent because of its simplicity (e.g compared to Anki).

It is probably the lack of simplicity in the design that prevents me from using DT for more than archiving. The Korouh book on smart note taking with DT is also not evidence for simplicity of using DT for that purpose, but the opposite.

Like most of us here, I use DT all the time This leads to an interest to extend the range for which one is using it. From the study of Roam & Co, I realised that DT is soo close to cover this use case as well … and hence the urge to share this observation here :wink:

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PS: you also rightly give Workflowly a mention.

They are an example of a tool that does many things Roam & Co do, and they are there for years, and have dedicated apps. Their implementation of outlining, boards, mirror nodes etc is fantastic. It is the simplicity of use (and yet lots of functionality) that impresses me.

As usual, there are downsides. In their case, its all chrome-based and the content is not stored in files locally (as Obsidian and Noteplan do).

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For me (so far) DT wins on grounds of extensibility, remembering that Luhmann’s original Zettelkasten grew to about 90,000 notes. I have no doubt whatsoever that DT can handle 800 or 80,000 notes as easily as it handles 80. None of the other applications discussed here have convinced me that they can.

Similarly, I don’t see much advantage to trying to visualize an entire zettelkasten at once. Rather, a more likely use case (for me) is to use DT to extract some topical subset of probably less than 100 notes, well within the ability of Tinderbox or Scrivener to visualize.

(There’s also a certain appeal to not needing to deal with yet another tool.)


Kourosh Dini was a guest on my Learn OmniFocus website shortly after “Taking Smart Notes with DEVONthink” was published. During his presentation, he shared some highlights from the book and an overview of the Zettelkasten approach. You’ll find the recording (free) here:


The discussion takes the usual route of us emphasizing how happy we are with DT, which is why we are hanging out here.

The bottom line of what I wanted to contribute is the view that Roam and Workflowly implement a list-based note taking approach that really is innovative, which is why I do think that the hype around Roam and Co, has a basis.

Have a look at a Workflowly video, like for example this one


The key to using Roam, RemNote and Workflowly is the design principle that you just start typing and it is while you are typing, the linking, searching, previewing, organisation etc takes place. The design is such that an astounding number of things can be realised while you are typing. What these guys manage is note taking (for meetings, for research), implementing a GTD approach and more, with a minimum of organisation of things in folders or using menus.

This is possible with this bullet point list approach, allowing you fold, expand, indefinitely indent, insert Kanban boards, images, code, equations etc., all accessible, searched, combined and linked by keeping with your fingers on the keyboard.

As simple as it is, or because it is so simple, this really is something worth noting before one can start philosophising about what to use this for including, GTD, PKM, the value of backlinking or why using Zettelkasten techniques!

This is why I watch that space with interest. While for task management, I would be happy to use a chrome, js and cloud based solution, if this surface could be used to generate files on my computer, I’d be very interested in adopting that workflow to generate notes and organise myself with it. I am also happy with what I have but rather than defending it, I see in those new tools some ideas that do things in a clever way, I feel.


Roam was first discussed on the Tinderbox forums back in December 2019 - https://forum.eastgate.com/t/roam-research-interesting-approach-to-note-taking/2713 - and was greeted with some enthusiasm and some scepticism. Some of the papers referenced there suggest that these ideas may have been around longer than one might think.

I rapidly decided that Roam was not for me, for a number of reasons. Among those, I’d sooner have a network of connections that I make myself rather than automatically generated connections. In my experience, too many connections leads to a mess, rather than being useful. Perhaps that is why I persevere with Tinderbox, despite finding it fairly challenging.

With all notetaking applications, I try to keep in mind the Collector’s Fallacy: simply having a note (or a copy of a paper, or whatever) doesn’t really do much to improve one’s understanding:

There’s also the closely related observation that students who take notes by hand tend to retain more: A Learning Secret: Don't Take Notes with a Laptop - Scientific American

Both of which suggest that a little bit of “friction” in one’s notetaking is actually good.


If you have the time I recommend watching this video. It is a very interesting way of using Roam to achieve Zettelkasten, which gives the ability to see related notes and also fosters digestion of the material rather than only reading it with a concept called “fleeting notes”. It is kinda hard to explain and a lot easier to see.