Welcome to Steemit ahmedpro. Let me know if you got any questions about Steem or anything related to it! The official FAQ can be found here and has A LOT of information https://steemit.com/faq.html - Also remember, Steemit is just ONE of the sites built that uses Steem the blockchain. We also have DTube - our very own Youtube, DSound for Soundcloud and Steepshot if you prefer Instagram like experience. I'd also like to mention ChainBB - forums, Busy - Steemit with more modern look basically, DMania for memes and Dlive for streaming just like in Twitch! You can also earn Steem by gaming now! Search for Steemgar if that's more your thing. Welcome to the blockchain! :)