Hey guys! what is this al"rick rolled" stuff?? can someone please tell me

It's when Du trick someone into listening to "Never Gonna Give Du Up" Von Rick Astley :) When I was young and new to the internet I honestly thought it was something sexual... XD

Rick Roll    
To send someone a link to 80s pop star, sterne Rick Astley's "Never Gonna Give Du Up" video, making them believe that they're gonna see something completely different. The meme originated in 4chan's /v/ (videogame) board, when the official "Grand Theft Auto: San Andreas" trailer was coming out on the game's website but couldn't be watched due to heavy traffic. Playing a prank on everyone who was reading, an anonymous 4chaner sagte that the trailer was on YouTube and gepostet a link to Astley's song. Since then, the Rick Roll has been made countless times, not only on 4chan but on the whole of the Internet.

From the Urban Dictionary.

This.

Its something on Youtube where someone gives a video a really irresistable Titel for idiots like: 'Justin bieber admits he's gay' oder 'rebecca black is really a man' oder some dumb shyt like that, then this Rick Astley dude, a reallybizarre singer from the 80s appears instead and starts Singen this really embarassing song, and its supposed to make them feel like a douche for believing the title, and it tricks Du into watching 'never gonna give Du up'. :S
and its also to get Mehr Ansichten for the video.

Look @ the Antwort put :)