Quick summary:

This is a movie about a news anchor at the end of his career who gets suicidal after being made redundant (on account of poor ratings) - he feels everything is bullshit (this is where the classic "I'm mad as HELL and I'm not going to take it anymore!" - monologue comes from) so he promises to commit suicide on national television.

The trouble is, because of this, ratings shoot through the roof and now his network is forced to keep him on in order to capitalise on this. They give him his own show where he gets to talk about what the marginalised/disenfranchised would want to hear about (i.e. "I don't know what to do about... but I know the first thing is - YOU'VE GOT TO GET MAD!").

Anyway, that's the basic premise. There's also a super-famous monologue by a Mr Moneybags type insider (which u/ConspiracyButtBoy quoted) where he basically lays out that there are no nations anymore, only corporations.

Network is easily one of the best satirical social-commentary movies ever made. Way way way ahead of its time and referenced in a lot of contemporary viddies on this subject matter. It's rightfully up there with They Live.