What is difference between equity account and Demat account?

I just registered for Equity account for 350, and i want to know if i need a Demat account also , and what is use of it. I am new to this Domain.

An Equity Trading Account allows you to trade in the F&O segment. If you’d like to trade in Equity shares too (intraday or delivery), you’d have to open a Demat account too.

A Demat account is similar to a bank account for shares. Whenever you buy shares in your trading account after T+2, these shares get deposited in your demat accont.