Investing in stock, also called equity or shares, means that you own shares or a smaller piece of share, that is issued by a company listed on a stock exchange, referred to as publicly traded companies. By buying company stock you essentially own a fraction of the company. 

There are two types of stock, namely common and preferred shares. And they differ from each other in that common shares give owners voting rights on company matters, whereas shareholders of preferred shares enjoy priority when dividends are paid. 

Investing in stock used to be the sole domain of financial professionals but the space has been opened up to everyday investors by investment platforms linked to the various stock exchanges.