CITO - Cache In, Trash Out - Since we are out and about in nature, it is suggested that we clean up around us during our cache find. Sometimes cachers do this, but when trying to get your numbers up, you may find you are in too much of a rush to do this so that is where the events come in. Once in awhile a cacher will host a CITO event in which the whole goal is to clean up a specific area. These are usually held at state parks, national forests, or local parks.
TFTC - Thanks For The Cache - This is simply another quick way to write something in the log, I often use it if I don't have much else to say.
SL - Signed Log - This is just a shortened way to write on the online cache page that your were there and signed the log.
TNLN - Took Nothing, Left Nothing - When the cache is large enough and you have the opportunity to trade out items, people like to let others know that they didn't make an exchange.
P&G - Park and Grab - This is used to tell that a find is quick and you can often park rather close to it.
FTF - First To Find - This is a favorite for everybody!! It simply means that you were the first to find a particular cache!!
DNF - Did Not Find - This is used when you were not able to locate the cache.
BYOP - Bring Your Own Pen - This is ofen written on the cache page when the cache is too small to hold a pen.
UPS - Unusual Pile of Sticks - When in the woods the caches are typically not buried but can be covered with leaves, rocks, etc. In this case you have a pile of sticks (obvious to the cacher) covering the cache container.