Investors who are planning to purchase stocks in the stock market would need to do a lot of research on the companies that they are interested in, as the performance of the companies would usually affect the price of the stock, but the values of bitcoin are generally affected more by the rules and regulations imposed on it which are set by the authorities of every countries, so I would say there is actually a huge difference between stocks and bitcoin.
Yeah all this research work is true but even if we don't go in all this detail we an simply understand it as how different are these both (stocks & bitcoin). When we are asked what is bitcoin? we say it is a cryptocurrency or a digital currency which makes it clear that it far away from stacks and stuff. It has it's own identity as a currency, just like you have dollar and pound sterling which are tangible or physical. I guess it is the simplest way to understand the difference. Also it is vulnerable to regulations because it is considered as a threat to the ordinary financial/economical system around the world.