As you said investing ang trading are both the same methods but I think trading is you can trade your altcoins or your holding anytime that you can get profit. In investing are you invest your money without knowing if you get profit or you gonna lose. Because some investment not so sure if you gonna be gain or not. But in trading if you are smart you can gain money even small profit.
Before we invest the money into any coins, it is better to analyze which coins that will have a chance to increase, and if we take a look at the market, bitcoin will be the best investment for a long time. We can use bitcoin too for trading because bitcoin can give us more chances to increase the money that we use in trading. Both trading and investing will produce more money for us if we can get the right coins, and so far, I used bitcoin for a long term investment while I also use bitcoin and altcoin to trade for a short and middle term trading.