知识 (zhīshi) is the general word for 'knowledge' — facts, information, and skills acquired through study or experience. It's broader than 学问 (xuéwen 'learning, scholarship'), which implies deeper academic study, and more factual than 智慧 (zhìhuì 'wisdom'), which is about good judgment. 常识 (chángshí) is specifically 'common sense' or everyday practical knowledge.