What is pre IPO shares?

The basic thing required to set up a company is funds or equity.To raise these funds the companies invites the investors to buy their shares & equities.The investors invest in the company just to get a high return.For instance an investor invested Rs. 5crores in a company.After few years the investor wants to take an exit from the company & thus the company plans a IPO for the investor & usually this information comes in front of the media.Nowadays awareness in public have increased a lot via social media,media people etc. so IPO get a lot of attention thus resulting in high subscriptions.