Android is an open source operating system developed by Google that uses a modified Linux kernel. It was founded in 2003 by Andy Rubin and later acquired by Google in 2005. The Android OS relies on Linux for core functions like security, memory management, and networking and allows developers to create apps using Java or other languages that are distributed through the Google Play store. While open source nature allows customization, Android can experience issues like unstable performance, battery drain, and security vulnerabilities.