See 5 and 120 for an explanation.

calkfreak83: Just to make things weirder, we should start saying "120d".

120d = "LOL!", just use 120d in replacement of it.
Nothing is compatible with a Mac! Not even viruses! 120d
by no_one_2000 August 11, 2004
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120d = lol!

lol! can be written as 101!
Mathmatically 101(binary) is 5(decimal). Therefore 101!(binary) is 5!(decimal)
The notation '!' is called factorial. 5! (factorial of 5) means 1*2*3*4*5 which is equal to 120. Since 120 is written in decimal form, a 'd' is added to the end of it to form 120d.

That's why 120d means lol!

(note: 120d has the exclamation mark included, 120d would mean lol!! with two exclaimation marks)
GodofJur ...and that's why 120d means lol!
dude wtf!?!
GodofJur 120d
dude math geek...
by GodofJur February 24, 2005
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