There are two types of knowledge: know-what and know-how. Know-what concerns itself with facts and conclusions. Know-how concerns itself with processes and techniques.
Know-what is memorizing a multiplication table. Know-how is multiplying any two numbers on demand. Know-what is recalling the events of Harry Potter and the Philosopher’s Stone. Know-how is reading that book, or any book.
Know-what tends to be specific, time-bound, theoretical, and context-sensitive. Know-how tends to be broad, timeless, practical, and durable. Know-what can usually be understood within a few intense hours of study. Know-how takes a lifetime to comprehend; it is more accurate to say that know-how resists comprehension, and is instead a daily refinement of imperfect understanding, an endless study. Know-what can exit the brain within hours. Once set, know-how settles in the marrow.
Formal education’s role is solely to train know-how. Know-what should be self-directed.
Unfortunately, outside of a few subjects (mathematics, elementary grammar, athletics), most education systems get this exactly backwards.