Over time, the things you like will accumulate and you can scroll through the list and pick posts to reblog which in turn will be reblogged by other users and generate a number of notes (visible with each post) that show exactly how many people either liked or reblogged the piece.

FORBES: Tumblr 101: Join The Reblogging Group

For example, instead of attempting to capture the attention of 18- to 34-year-old consumers solely through print or online advertising, a so-called influencer might turn to Tumblr and its cult of product obsessives those who blog and reblog images from fashion label lookbooks or commercials masquerading as short films to initiate consumer interest on a more casual level.

FORBES: Selling The New Cool: Inside The World Of 'Influencers'