In AI, a 'skill' refers to a modular add-on or extension that enhances an AI agent's capabilities, allowing it to perform specialized tasks beyond its core functions. Skills can be independently developed and integrated, enabling the AI to access new data sources, interact with external applications, or execute specific commands. This modularity makes AI systems more flexible and adaptable, as users or developers can customize and expand the AI’s abilities without altering its foundational architecture. For example, a virtual assistant might gain a 'calendar skill' to manage appointments or a 'weather skill' to provide forecasts. Skills are crucial for tailoring AI agents to diverse user needs and environments.