In the online trading world it could be crypto future trading or forex future trading there is a good and perfect time where there are a lots of trading and biding are running and taking place, those times are when the time zone of those developed countries merge and overlap at this time many online investors invest their money and they trad and yeah there will be a lots of profit and also a lots of price variations so it needs some focus, but the bad time for trading is on a Friday night, most of the times if i start trading on Friday night then there will be no much change and the price variation is very slow on crypto. and for forex trading it will be close at the weekend.