Both stock market and bitcoins are different from each other but they also have some similar points . The only similar thing between them is that there is a level of risk in both of them. Stock market is supported by government so it is slightly more safer than government whereas bitcoin is not trusted that much.
But the the probability of getting profit through bitcoins is comapritively high and fast as compared to stock market.
Both bitcoins and stock market are based on predictions and risks which takes luck and expertise in order to get some good profit.