Template:Didyouknow

...that someone on the Left for Dead 2 team has a thing for lift bridges?

...the tattoo on Francis' shoulder can also be seen on the ring Nick wears on his right hand possibly hinting a connection with the two.

...the Hunter doesn't have eyes. Despite this, he can still somehow see.

...the coffee mugs found in various levels that state "Layoffs anyone?" and "What's Sleep?" are imported directly from Valve's Counter-Strike?

...in the second level of Dead Center, Large Decontamination Trailers can be seen with text on the side humorously reading "Disease Emergency Assessment Dispatch", or D.E.A.D.

...Bill is the only one in the introduction video to wield a tier 2 weapon.

...the Charger hanging in Swamp Fever is done so in the shape of a Lambda, which serves as the logo for Half-Life?

...there was originally an Infected in Left 4 Dead called the Screamer. It would wander around until spotting the Survivors and would then run away and utter an ear-piercing scream that summoned a horde. He was later cut and his ability was passed on to the Boomer.

...the pills used in-game were based directly off of the Target brand of Ibuprofen?

...in the original development, there was no linear path in Left 4 Dead campaign chapters and Survivors were free to roam the city before finding the safe room? This however proved to be too confusing as play-testers found themselves lost amongst the levels.

...an X-ray found in Mercy Hospital bears a striking resemblance to that of a Spitter?

...Francis has a Lambda shaved into the right side of his hair?

...In the very first trailer of Left 4 Dead, Bill was killed by a Smoker, something that would be quite a difficult task considering the Smoker has a weak claw attack.

...Bill's trademark cigarette never goes out unless he's either dead, or at the beginning of the introduction video?