"What is the usage of something?" usually asks for a thing's purpose or for a how-to: "How do you use that?" would be an alternate way to say it. "What is the use of something?" can mean the same thing but is often used in a rhetorical way that means that the thing has no use at all. Example: - "We are lost in the desert but we have a sweater." - "Well, what is the use of that?"

Oh! What to do?! I have a really bad experience with ooVoo so sorry but I'll not be using it againg! If u have Skype or sth It's OK for me. And, sorry but I gotta know u better to chat with u sorry for that.

Hi! I'm Colt in New York. I'm glad to help you improve your spoke English. I use only ooVoo to teach and help. Please download and make an account and let me know your ooVoo ID. We can then begin! Thanks! :)