Udemy is the world's largest online learning marketplace in 2026, offering over 210,000 courses from 75,000+ instructors in 75+ languages, with millions of learners enrolled. It features individual course purchases (often on sale), a Personal subscription plan for curated access, and Udemy Business for enterprises. Popular for tech, business, design, and AI skills, it supports self-paced learning with certificates, mobile apps, and lifetime access to purchased courses.