Hotmail and Gmail are both online email services. The core difference between the two services is that they are each owned by a different company. Hotmail is owned by Microsoft, and Gmail is owned by Google. Both services are free, and each offers POP3 support. A typical Hotmail address ends in the domain name "@hotmail.com", whereas a Gmail address ends in "@gmail.com". To learn more about Gmail, visit: http://www.ask.com/wiki/Gmail. To learn more about Hotmail, visit: http://www.ask.com/wiki/Hotmail.