TOSCA, which stands for the "Topology and Orchestration Specification for Cloud Applications," is an open standard language and framework designed to simplify the management and deployment of complex, distributed applications in cloud and hybrid environments. Developed by the OASIS consortium, TOSCA provides a standardized way to describe the structure and behavior of applications and their components.

At its core, TOSCA defines a model that represents the architecture of an application, including its components, relationships, and the orchestration logic needed for deployment and management. This model is typically described using YAML or XML files, making it human-readable and machine-executable.

One of the key advantages of TOSCA is its portability. Applications described in TOSCA can be deployed across different cloud providers and platforms without the need for significant modification. This is achieved through TOSCA's abstraction of infrastructure details, allowing for greater flexibility and interoperability.

TOSCA also supports the automation of application lifecycle management, including provisioning, scaling, and decommissioning. It enables organizations to create reusable templates and define policies for how applications should behave in different environments and under various conditions.