If you consider the market a casino there is no difference. Buy low sell high. But if you approach the market like an investor you try to estimate the intrinsic

If you consider the market a casino there is no difference. Buy low sell high. But if you approach the market like an investor you try to estimate the intrinsic value of the assets and liabilities of a company, their cash flows, their growth prospects, and their management. Then you find those companies where the market price doesn't match what you think the business is worth and you go long/short those businesses where you think the mismatch is the greatest.