https://steemit.com/steemgigs/@steemgigs/free-steemgigs-for-every-steemian-having-cheetah-issues-avail-of-this-steemgig-for-free-every-newbie-steemian-is-invited

It simply means that you account has grown a level up. you have like up to 1k steem, so you now have the luxury of choosing with how much percentage you want to upvote a post. This helps you maximize the use of your voting power