Upwork is an online platform that connects businesses with freelance professionals. Companies can post projects and invite freelancers to submit proposals. Once a freelancer is hired, they complete the work and submit it to the client for approval. Upwork handles all payments between the client and freelancer and also provides tools to help manage the project, such as real-time chat and video conferencing. Upwork is a convenient way for companies to find skilled professionals from around the world, and for freelancers to find new clients.