To release something or someone is to set it free, like a caged animal or a prisoner. “I shall be released” is a famous refrain from a 1967 Bob Dylan song that has come to symbolize political freedom around the world.
Release, which is a noun and a verb, has many different meanings. As a noun, it can mean a liberation, an unfastening, or the condition of being made available, like a movie or a CD. “When is the new Spiderman movie being released?” you might ask your best friend. As a verb, it can mean to relieve of suffering or obligation, like a debt. But it can also mean to lay off from a job, or surrender. “Release me from having to watch this terrible movie!” you could end up saying about the 16th Spiderman sequel. And who would blame you?