Modern applications are built on open source. Your team may write the business logic, but most applications depend on hundreds or thousands of third-party packages, frameworks, libraries, plugins, and transitive dependencies. That is why engineering teams often ask: what is software composition analysis , and why has it become a core part of application security? Software Composition Analysis , usually shortened to SCA , helps teams identify open source components inside their applications, detect known vulnerabilities, understand dependency risk, and find safer versions to upgrade to. If your application uses package-lock.json , requirements.txt , composer.lock , pom.xml , go.sum , or an SBOM , an SCA tool can analyze those files and show which dependencies create security risk. This guide gives you software composition analysis explained in practical engineering language.…