Name one millionaire who does not own stock ( Equity share ). be it Elon Mask, Ambani, Jeff Bezos, etc. they are businessmen though. But Jhunjhunwal, Warren Buffet are got rich only by investing money in stock.
Stock Preferably known as Equity share is a Fraction of ownership of that company or entity. Equity means Asset-debt .

“if you have built castle in the air, your work need not be lost; that is where they should be. now put the foundation on them” —Henry David Thoreau Walden
A wonderful quote for share market investor. Whenever we think about share market we heard about money or for some people it’s a money making machine. But it is a hard nut to crack without proper knowledge.
What is the stock (equity share)?
Equity share means the fraction of ownership of a company what you can buy and sell without getting involved in company work.
How can I buy share?
you can buy share of a company if the original owner/owners of the company release his share privately or through exchange for the sake of money. If you have demat account( as for money to hold we have bank account) , you are good to go for buy and sell share through an Exchange.
What is the exchange?
exchange is where share can be traded. For example BSE(Bombay stock exchange), NSE National stock exchange). Newyork stoke exchange, Shanghai stock exchange and many more. This is the place where company offer their share called IPO(initial public offering).
Why share Price are fluctuating?
The price of the stock(Equity share) fluctuates mainly because of the supply and demand theory. Like we know if demand increase of a particular commodity, but supply remains the same or lower then the price of that commodity increases. But sometimes share prices may be manipulated (especially penny company ) by Pump and Dump method. But SEBI always has an eye on them and eventually then ends up in jail.
How Can I open a Demat Account ?
All you need to open a demat account for share to sell and buy and make some money out of it. So you have to register with any brokerage firm, i.e. Samco, angel broking , Zerodha etc. You need to fulfil the requirement. Among them samco what I personally use is very cheap, lowest brokerage in the industry and also they provide free first 20 trade free of cost . Then they charge Rs 20/- per order.
It’s awesome