I was taught to use <> for "not equal to," but kids these days think != looks 'cooler' I guess. (Plus, with xml languages that use < and > for other purposes, like we do here on FR with HTML tags like <P> for new paragraph, using <> isn't even possible.)
Back in my day, we programmed in machine language, hand compiled from object code, loading the programming code one byte at a time using toggle switches, and we liked it!
If I’m doing, say, a simple database equation on my PC or Palm, I use <>. That’s what’s available. But I’ve always considered the combined “=\” mark to be the default “not equal to” symbol. The != is a new one for me. Oh, well. I’m not into Kool...