making dll file problems please help me

hello.

I am very new to visual basic i got 6.0 version i know my way around it and still don't know how to make a dll. because i have this problem, i'll explain

i downloaded a dll called "msnslang.dll and when i added it into my msn messenger root folder it changed some of the msn script and i was baffled and jelous because i wanted to make one but did not have a clue and i wondered how this bloke done that. did he open the dll in some sort of viewer or something or edit the dll through vb. i really esant to know but can't explain it very well but if anyone knows what i am talking about please help me thnax

cya,
micky