住 (zhù) is an ideographic compound. The left component 亻(rén, "person") suggests a human subject, and the right component 主 (zhǔ, "master/main") lends the phonetic value and hints at the idea of being rooted or settled. The character has been used since the oracle bone script era to denote dwelling or halting in place.

In China, 住 is used both for permanent residence (住在北京 "live in Beijing") and short-term stays (住酒店 "stay at a hotel"). As a resultative complement, 住 can mean "to hold firmly" or "to stop something," as in 记住 (jì zhù, "remember / keep in mind") — a form every learner will encounter quickly. Don't confuse 住 (zhù, to live/stay) with 注 (zhù, to pour/annotate) or 助 (zhù, to help); they share the same tone and romanization but are completely different characters.