A package manager is a tool that automates the process of installing, upgrading, configuring, and removing software packages. It simplifies software management by handling dependencies, which are other software components required for a package to function properly. Popular examples of package managers include npm for JavaScript, pip for Python, and apt for Debian-based Linux systems. Package managers typically use a central repository to store and retrieve software packages. Users can easily search for, install, and update software with simple commands, making it more efficient than manual installation. This helps maintain system stability and ensures that users have access to the latest software versions.