I am pretty new to these forums and I have seen these things in a lot of the posts on here and I have no idea what they mean.

icecream.gif' class='bbc_emoticon' alt=':icecream:' />

I know they change some of the words in them but what in the world is this.

They're BBC code for the smileys that the forum uses. The forum software was recently updated (some would say "borked" is the better term), and on a lot of older pages now, the smileys don't render correctly; the code for them is displayed instead.

That's the code for an emoticon. Either your browser does not support this, or the poster used a third party or even a local sourced emoticon so it won't show up on your system. Or, the last software update caused this.

You can enable/disable emoticons in your profile.

I've seen those in old posts, in recent ones they work fine. Maybe the emoticon codes or system was changed in the update?

That's where some of the emoticons in posts from before the forum update a couple of months ago weren't converted properly. Some of them were converted properly, but it seems that some weren't. It's possible it's partly due to the issues that occurred during the update process.

As others have said. The code is seen instead of the emoticon, but only in old posts. That icecream code looks like this when it works properly: