Hey Abhishek,

You can see this as an analogy with classes and objects in OOP. The WebBlock you define is like a class, but everytime you place the webblock inside a screen (or another webblock) it's like defining an object of that class, so every webblock is independent of the other webblocks,  it's just a piece of reusable UI & logic that can be independently used in different parts of your application.

Hope I made it a bit more clear.

Regards,
Bogdan

Hi Abishek,

A block is just like a template, it doesn't exist yet unless it's used. So every time you use a block, OutSystems adds it to the screen it's used on, so every use is an "instance".

This is a definition of "instance":