An increasing number of people use the term, especially young people, in informal contexts and oral language as a synonym of something that is not pre-established, that is open, varies, by chance, arbitrary, and even strange. But it is also a synonym for something normal, basic, or tedious.
It also refers to an event that occurs without explanation, unexpectedly, and casually.
For example, a random plan (open, varied), a random song list (shuffled), a random night (strange), a random boy (ordinary, anybody).