Upwork, formerly Elance-oDesk, is a global freelancing platform where businesses and independent professionals connect and collaborate remotely. In 2015, Elance-oDesk was rebranded as Upwork. Upwork allows clients to interview, hire and work with freelancers and agencies through the company's platform. The platform now includes a real-time chat platform aimed at reducing the time to find and hire freelancers. The platform offers a time sheet application that tracks time and takes screenshots while the freelancer is working (Wikipedia).
Self-description (from their website)
Hire freelancers, make things happen. Grow your business with the top freelancing website. Hire experts from anywhere.
Skill levels and worker requirements
Freelancers get paid by the hour, or a fixed price for the entire project. On fixed-price jobs, there is licensed escrow service to release funds as pre-set milestones are met.
Platform revenue derived from
Upwork earns a commission on all of the jobs. The percentage is calculated depending on how much you’ve earned with the contractor. For the first $500 you earn, Upwork takes a 20% commission. Then, from $501–$9,999, Upwork takes a 10% commission. After you’ve billed $10k to a client, Upwork only takes a 5% commission.