In roulette, bets are divided into two main categories: inside and outside bets. Inside bets focus on specific numbers or small groups and include various types such as straight-up, split, street, corner, and line bets, which generally offer higher payouts but have lower winning odds. Outside bets, placed on broader categories, include wagers on red or black, even or odd, and high or low numbers, along with columns or dozens. These bets provide better odds of winning but usually come with lower payouts.