Can someone please help me watch youtube videos?

i click on the video but it says exactly this:Hello, you either have JavaScript turned off or an old version of Adobe's Flash Player. Get the latest Flash player. i copied and pasted! this is exactly what it says! so i just installed the ltest version and it still didn't help! i tried looking in google but it just says install the ltest version and i did! IT STILL DOESN'T WORK dammit! I installed it like 20 times already! please help!