Annotation:

The @future annotation is used to designate a method as a future method in Apex.

Asynchronous Execution:

Future methods are executed asynchronously, in a separate thread and separate transaction, after the completion of the current transaction.

Use Cases:

Future methods are commonly used for tasks that might take a significant amount of time to complete, such as making callouts to external services, batch processing, or any operation that could potentially exceed the time limits of a synchronous transaction.

Governor Limits:

Future methods have their own set of governor limits, separate from the limits applied to synchronous transactions. This allows for better resource management.

Invocation:

Future methods are typically invoked from within synchronous contexts, such as triggers, Apex classes, or Visualforce controllers.

Syntax:

Here is a basic example of a future method in Apex:


Limitations:

Future methods have some limitations, such as not being able to return a value, not supporting the same set of parameter types as synchronous methods, and not allowing inner classes with methods annotated as @future.

Usage Considerations:

Developers should carefully consider the use of future methods and be aware of their limitations. Depending on the specific use case, other asynchronous processing options, such as Queueable Apex or Batch Apex, might be more appropriate.

In summary, a future method in Salesforce is a way to execute code asynchronously, providing a mechanism to handle long-running tasks and prevent them from impacting the responsiveness of the user interface or breaching governor limits associated with synchronous transactions.