The description of Alcohol Free Beer by LordOmar that "Beer that has had the alcohol removed from it (or never put in it)" is not entirely correct. Alcohol isn't a separate ingredient added to nomal beer, but produced during fermentation (anaerobically) of mainly malt and hop by brewers yeast (a specialized Saccharomyces cerevisiae).

To produce "alcohol free beer", the manufacturer uses a genetically modified brewers yeast strain where the metabolism for alcohol production is suppressed.
I used the quotation marks, as alcohol free beer isn't entirely alcohol free: it still contains 0.3-1.5% alcohol, depending on the brand. Attempts to produce beer really without alcohol failed because during the degradation of starch to alcohol other aroma components are produced as well (a linked metabolism). Without those specific processes, the beer didn't taste like the real stuff at all and therefore is never sold.

Although it isn't a complete shame anymore to drink alcohol free beer, I wouldn't say it has status to do so. This may be because the Dutch comedian Youp van 't Hek introduced the term Bucklerlul (translated a Buckler dickhead): only a loser doesn't do what s/he really wants to do because of some lousy, unfounded reasons.
"Be a man, drink real beer and get pissed, or stick with the soft drinks."