Make is a tool that automates the building of software by tracking dependencies between files and only rebuilding components that have changed. It reads build instructions from a makefile to determine what needs to be built. Make traverses the dependency tree of a project, rebuilds out of date or missing components, and handles dependencies between files and components. While powerful, makefiles can be difficult to write and debug, and Make has limitations for languages like Java that don't expose dependencies in source code. Alternatives like Apache Ant provide similar functionality through XML build files.