Topcoder is a crowdsourcing platform for software development that connects corporate clients with a global community of over 220,000 members from 200+ countries to deliver projects, resulting in 30-60% cost savings compared to traditional methods. The platform leverages a competition-based methodology to enhance quality, speed, and reliability in project delivery, allowing clients to access skilled resources on demand. Key features include a large catalog of reusable software components and a robust quality control process built into the competition structure.