Open Worldwide Application Security Project (OWASP)

OWASP is the community-driven organization that keeps the internet slightly less terrifying by cataloging all the ways applications can be exploited and teaching developers how to not make those mistakes. Their most famous creation, the OWASP Top 10, is essentially a “greatest hits” album of web application vulnerabilities — SQL injection, cross-site scripting, broken authentication — that gets updated periodically to reflect whatever new and creative ways attackers have found to ruin everyone’s day.

Beyond the Top 10, OWASP maintains a sprawling ecosystem of projects: testing guides, security cheat sheets, vulnerable-by-design training apps like WebGoat and Juice Shop, and tools like ZAP (Zed Attack Proxy) for automated security testing. The organization operates as an open community where security researchers, developers, and organizations collaborate to raise the baseline of application security across the industry. Their resources are free, vendor-neutral, and referenced in compliance frameworks worldwide.

Why it matters: OWASP gives every development team — regardless of budget — access to world-class security knowledge. Their guidelines shape how organizations build, test, and audit applications, making the OWASP Top 10 practically required reading for anyone who writes code that touches a network.