Ico which is initial coin offering this is an avenue that new project entering the cryptocurrency market use to advertise their token for possible investors. During and ico you can have pre-sales and crowd sales, some ico has a soft cap this is the minimum target and hard cap this is the maximum target some ico also organises bounty program to help propagate their project even more. Ico has really been useful in the cryptocurrency world.
You can enhance your research with this links
https://www.investopedia.com/terms/i/initial-coin-offering-ico.asphttps://bitcointalk.org/index.php?topic=1438371.0