The power of your vote is decided by the amount of steem power or sp you have in your wallet. The more sp you have the bigger the rewards pool that your vote carries. So for example I have 1337 sp this gives my vote the power to reward like .07 sbd.
Oh one other thing only use the tag introduce yourself once it is designed to be used for new people one time. I got feedback on my post I did after one month not to reuse that tag.