It's common for me to read something, and forgot it even existed. I can't look it up unless I know it exists. With flash cards, I am reminded that it exists every once in a while.

As an example, here's a simple card: What is the recommended way to traverse all the files (including subdirectories) in Python?

Answer: scandir and not os.walk

os.walk is my standard goto. Then I learned about scandir, but kept forgetting that there was a better alternative to os.walk. So I made a card for it.

The other answer, of course, is speed. If I'm going to Google "what is the alternative to os.walk?" or something similar every time I need it, it adds a lot of friction and I simply won't bother. And no, I don't do this often enough that looking it up each time will force it to become ingrained.

And frankly, when you do math/physics, you do need a number of concepts in your head. Solving a complex problem requires multiple parts/stages, and solving requires you to have them in your head so you can put them together. My biggest mistake when I was in grad school was thinking I could get by without memorizing. It worked fine for undergrad level math, but it was a real problem when I took higher level courses. The professors were split on whether memorizing is a good idea, but the fact is the professors used this stuff a lot more than I did.

Thanks for providing these details.

For your Python example I'd just use a snippet. On the other hand, Google's pretty fast and always updated.

It's all a personal trade-off I guess. I wouldn't say it's common for me to forget I knew something. But maybe the cost of creating, maintaining, and reviewing card decks is worth it for you.

If I may ask, how do you know it's uncommon for you to forget you knew something?

E.g. when looking over old notes I remember most stuff.

What use is a snippet if I forget it exists and that there is a better way?

You'd probably remember a snippet if you made it. If not, there's autocomplete.

I wouldn't. Pre-flash cards, it was not unusual for me to review notes I had made years ago and rediscover things. And then forget they existed all over again.

Unknown unknowns. Knowledge availability is another big one.

I used Anki to learn molecular biology. I work in bioinformatics and understanding molecular pathways means I can more fluently build hypotheses with colleagues. Without having memorized these pathways, unknowns unknowns and lack of knowledge availability would prevent a lot of discovery.

Because it helps you quickly connect those facts together into a larger idea later.

If the facts are in your head, you can make a connection between them. If they are in different places on the web, unless someone else already linked them for you, they remain separate.

Can you give an example?

Anki is used a lot in medical education. There's a lot of small details, and you can string them along to form the big picture. An example is going from symptoms -> diagnosis -> treatment options -> drug side effects. You can't just memorize use drug X for Y, but you incorporate information that you know to formulate the best plan. Suppose the patient has kidney disease - you've memorized X is nephrotoxic so you find another treatment.

I will say this is easier for some and harder for others. I've noticed some people have a lot of difficulty recalling facts without a specific cue when using Anki. It's best used with traditional learning, but you can focus more on the why.

Sure there's a lot of memorization in medical school but I'm more interested in computer science, the context of the article.

I guess people shouldn’t study history anymore when they can just look up things on the web

There's more to learning history than memorizing facts.

Competency and efficiency.