Why would Any She pretend to be a He?

Why do women sometimes pretend to be men when talking in chat rooms or using chat programs? Is it because some immature males treat all women like second-class citizens or brainless bimbos so that you have to pretend to be male to get listened to? Or is it just curiosity about how men talk to other men? Or how other women talk to men?

Someone who plays in a game I run asked if a friend of his could join in, and then put me in chat program contact with her. We talked over the Internet for a while before meeting in the flesh. While chatting, she admitted that she sometimes pretends to be male online. I haven