Overview

Actions allow you to build custom development tools for Force.com applications.

Actions are about “getting things done” in Salesforce. They encapsulate a piece of logic that allows a user to perform some work, such as sending email. When an action runs, it saves changes in your organization by updating the database.

Actions are easy to discover and use, and also easy to understand and implement. Every button and link in Salesforce can be considered an action. A consistent Actions API and framework supports the creation and distributed use of actions throughout Salesforce. Actions are available in the REST API.

These are the major types of actions:

Type	Description
DynamicAction	Dynamic actions, also known as invocable actions, can be invoked from a common endpoint in the REST API. They provide “describe” support – a programmatic mechanism to learn about all dynamic actions on the platform. There are two types of dynamic actions. Standard action A standard action is ready to use right away. The work it performs is predefined, along with its inputs and outputs, and they’re available in every organization. Custom action A custom action must be created by you. That is, it requires a definition. For example, to use an Apex action, you must create the Apex class method for the action.
QuickAction	Quick Actions, formerly known as Publisher Actions, are backed by page layouts and make it easy for administrators to configure an action to create or update a record. The API always works with an sObject.
StandardButton	Standard buttons are URLs allowing users to either go to another page (for example,the Edit page) or accomplish some task (for example, lead conversion).
CustomButton	Custom buttons are URLs that an administrator can specify and when included on a page and clicked, will redirect a user to that URL.

To call an action from a flow, use FlowActionCall, as described in the Metadata API Developer’s Guide.

Force.com Actions Developer's Guide

Overview