Organizing the Flashcards

I can just read books and I'll see a new word and I'll look it up and then I'll forget it. But if I keep reading more books, I will see that word again later some other time. It's kind of a natural way of getting repetition, of getting review. So how do we organize? There's the old way of flashcards, paper flashcards, right? Another kind of flashcard system we now have are different apps on your computer or phone. Anki is probably the most popular A in K I, Anki.