Frontrunning is a service provided by steembottracker.com. It enables users to upvote content to be upvoted by big bots. In that way, you can earn a sizeable chunk of curation rewards based on your vote weight and timing. This bot will resteemed on steemit account page for other users to upvote it. This provides more time for users to actually read the posts and upvote them only if it suits them.