What is Remote Action in Salesforce/What is the use of this action?

Hi Sushant,

JavaScript remoting in Visualforce provides support for some methods in Apex controllers to be called via JavaScript.

JavaScript remoting has three parts:
1. The remote method invocation you add to the Visualforce page, written in JavaScript.
2. The remote method definition in your Apex controller class. This method definition is written in Apex, but there are   few differences from normal action methods.
3.The response handler callback function you add to or include in your Visualforce page, written in JavaScript.

For more info on why we use Javascript remoting, refer to this blog.

Hope this helps.

The RemoteAction annotation provides support for Apex methods used in Visualforce to be called via JavaScript. This process is often referred to as JavaScript remoting. This action function in salesforce allows user to access any method from any class through javasrcipt methods.

JavaScript remoting in Visualforce provides support for some methods in Apex controllers to be called via JavaScript. Remote method invocation you add to the Visualforce page, written in JavaScript.

Thanks