Java Platform, Standard Edition (Java SE) is a widely-used software development platform that provides the core functionality for building and running Java applications. It includes essential libraries, tools, and a runtime environment, enabling developers to create desktop applications, server-side applications, and more. Java SE is part of the larger Java Platform ecosystem, which also includes Java Platform, Enterprise Edition (Java EE) for enterprise applications and Java Platform, Micro Edition (Java ME) for mobile devices. Java SE is known for its portability, allowing applications to run on any device with a compatible Java Virtual Machine (JVM).