What do the following extensions mean?

.com

Company

For Example - https://www.youtube.com

.gov

Government

For Example - https://www.usa.gov

.net

Network

For Example - https://www.asp.net

.sch

School

For Example - http://adnoc.sch.ae

.ac

Academy

For Example - https://www.ox.ac.uk

.co

Co-Operation

For Example - https://www.go.co

.edu

Education

For Example - https://harvard.edu

.org

Organisation

For Example - https://en.wikipedia.org