ICO's are initial coins offering.
Not worth your time, good bait to scam newcomers though.
I agree with you in the fact that some ICOs are just cashgrabs, but there are a few that actually looks legitimate. You just have to filter through all the bullshit to find some good ones. I personally don't invest in ICOs though, as bitcoin and ethereum are still my go-to's.
To OP: looks like you really don't know what you're doing right now. Don't be lazy and read alot of posts/threads about ICOs here in bitcointalk and other articles on other sites. Those questions of yours has been asked for a good number of times already that it seems pointless to answer the same questions every time.
bitcointalk.org: What is ICO ?https://www.cryptocompare.com/coins/guides/how-to-avoid-scam-icos/https://icotracker.net/