Depends on you po.
Short Term Investments are Riskier. But offers greater Returns if you do it right and pay attention to the volatility of the market. This requires skills and a good amount of your time for this to work as this relies on the short ups and downs of the stocks in the market. (Higher Reward -- Greater Risk)
Long Term Investments are safer, but not one without Risk. This is the way to go if you have a job and just wanted to let your money grow with little attention to the market.