What's up. HTML newb here. :I

So I'm trying to get a picture to show up in my profile/forum signature but can't get the HTML to work. I'm doing the

< img src = "PIC'S URL" >

thing (without the spaces, of course) but my picture won't show up... I tried doing the alt thing and giving it a different source, too, but still nothing. D: Is there a particular source that works the best for HTML? I tried taking the picture off deviantart and straight off my computer, but neither of them took. Like, should I upload the picture somewhere else and take the URL from that? Or am I doing something else completely wrong? Haha

I hope that all made sense, sorry if it was unclear. :[