The main character, or at least the character that starts and ends the book is Yossarian. Yossarian is a pilot during World War 2, and as best as I can tell, spends the bulk of the book trying to get out of doing more of it, while also dealing in the black market with military supplies.
I say above, 'as best as I can tell' because everything is out of order. Wait, that's not quite fair. The stuff that happens in the 1944 narrative is mostly in order. Two major sections of the book are also in flashback, and those are definitely not in order.
Each part of the story is retold from the perspective of someone else, and some of the basic facts don't line up. This, I am told - over and over again - by well meaning friends and acquaintances, is entirely the genius of the book. It's a masterpiece because of the very ways it doesn't make sense.
Here's the thing, I can see how the absurdity of war plays out here. I can even see how the best of that old show M.A.S.H. was probably influenced by this book, but I am a reader that needs a solid narrative. I actually think this book is something I'd even enjoy if someone simply put it all into a single timeline order.
I'm here to stand on this imaginary hill and say that it is perfectly fine to hate this book for all of the reasons your friends think its great. I certainly do.
Content warnings for violence and rape. Those things, too, are what make this book so powerful, and make me want - even more - to avoid it.