While gambling does have to have a way or tactic when Playing, but most gambling just takes a little bit of luck.
But if you don't have skills of trading or don't know how to get latest market news about your investments then it is also similar to gambling. Because people are investing just by thinking that prices may go high and that makes it similar to gambling. So if one wants to trade then better learn trading basics and always start with a small amount until you become experienced.