In my country all companies are having a 3 months probation period, when they can fire you without notice or reason, as the laws allow it.
I think, to sibling poster's point, there's a massive difference in approach and reality to both company and employee in "hop on, maybe we'll fire you if it doesn't work" (probation), vs "hop on, maybe we'll hire you if it does work" (trial).
I for one am not at a point in my life where I'm even remotely interested in trial hire, either as hiring manager or an employee - FWIW, YMMV :)
A trial period could be the same thing but it could also be "We usually extend permanent offers to about a third after the trial period." If it's a formality that may be one thing. If it's an extension of the interview process, that's something else.