A stored procedure is a predefined block of SQL commands stored and executed inside SQL Server. It is especially useful for repeated, complex or business-critical database operations.

One of the main benefits is performance. Stored procedures can reduce network traffic, centralize query execution and benefit from execution plan caching in many scenarios. When the same operation is called from multiple parts of an application, stored procedures provide a consistent access point.

Security is another advantage. Instead of granting direct table access to application users, you can allow execution of specific procedures. This provides better control over data access.

Stored procedures also improve maintainability when used carefully. Some data operations can be updated in the database without changing application code. However, moving all business logic into the database is not always ideal. A balanced approach is usually best.