The taxability and ITR Form to be filed for shares of a listed and an unlisted company is different.
If the shares of a company are traded on a stock exchange, then it is a listed company. In India, shares in a listed company are traded by using a Demat account.
Whereas, the shares and securities of an unlisted company are not listed on a stock exchange. Unlisted securities are also called over-the-counter(OTC) securities.
Read more about the types of companies in India.