What caliber is 7.62, and how does it compare to other popular calibers like 9mm and .308?

The 7.62 caliber typically refers to a 7.62mm bullet diameter and includes cartridges like 7.62x39 and 7.62x51 (.308). Compared to 9mm, 7.62 calibers are more powerful and designed for rifles, while 9mm is typically used in pistols. .308 is another 7.62 caliber with higher energy and range than 7.62x39.