What is the definition of "necro"...

[Le Compilateur]

I'm very new to posting on forums. I've committed a lot of what are called "necros" (if it is a bad thing, I apologize) and I would like to know what that means.

[Survivor]

Posting in threads which haven't been posted in for a (long) time with irrelevant information.

[David]

It means raising a dead thread, bit like necromancy just with threads not zombies.
What counts as a 'dead thread' depends on both the thread and what your adding, a troubleshooting thread from 2 years ago is stupid to revive, but a still relevant guide to which your adding some new and relevant info to is a more gray area.  If its a sticky then its fair game.

In general the test is, is what your adding relevant to that thread, or that topic in general.  If the latter then its probably worth starting a new thread if there's none from the past month.  (Assuming there's need for another, some topics are just done to death.)
Where the 'past month' threshold comes is a matter for much debate.  Some people say a week of no posts and it should never be touched ever, others think months and its still cool.

[doomagent13]

Possibly a better guide would be whether or not it is on the front page of its subforum...

[David]

Possibly a better guide would be whether or not it is on the front page of its subforum...

Which brings us back to the differing opinions thing, I know forums where threads are off the first page within hours.  I also know places, such as the servers bit here, where there are posts back 2 years on the first page.

[Le Compilateur]

Ah, thanks for the info. I will be more careful next time I post something.

[Kaleo]

SMF gives you a warning if you try posting in a thread that hasn't been posted in in 7 days, I think...

[Le Compilateur]

SMF?

[Kaleo]

This forum system...

http://www.simplemachines.org/

[Le Compilateur]

Ah thanks.

[player1]

[Le Compilateur]

Nice pic. Kinda gruesome though.