What bidding system do you use? The most popular in the USA is Standard American. According to Wikipedia:
Standard American is a widely used bidding system for the game of bridge in North America and elsewhere. Owing to the popularization of the game by Charles Goren in the 1950s and ’60s, its earliest versions were sometimes referred to simply as ‘Goren’. With the addition and evolution of various treatments and conventions, it is now more generally referred to as Modern Standard American. It is a natural bidding system based on five card majors and a strong notrump; players may add conventions and refine the meanings of bids through partnership agreements summarized in their convention card.