Knowledge is the second category of learning. We master knowledge by reading, writing, and discussing: terms, concepts, facts, syntax, APIs, research, commentary, history, opinions, insights, designs, and so on.
Knowledge can also be considered wisdom from having mastered several skills and seeing the bigger connection between them.
You use knowledge every time you make any decision. Making sure you have accurate, relevant knowledge is crucial in the field of technology—almost as much as for medicine. A good technologist spends at least an hour a day reading to informed.