Law Spam

No, we are not talking about a luncheon meat here. Spam is the repeated use of a phrase, command, or channel that causes screen scroll for others. Basically ANYTHING that causes excessive/irritating screen scroll can be considered spam.
Not only is spam considered rude, but excessive screen scroll can interfere with the game play of anyone seeing it (not to mention combat situations).
The game will tell you to PUT A LID ON IT and force-quit you after the 20th repeat of a single command. (If you don't know what this means, go to a room that no one else is in and type save then type VIS 21 times, or once followed by ! 20 times).
However; the following are also considered spam:

to use the same phrase over several different channels

moving a large number of items into and out of a container in a, crowded, non-storage room

using multiple characters to chat the same message at the same time

making charmed mobs or pets to cause screen scroll through movement or orders

In addition, unsolicited advertisements of any sort (Including advertising another mud on public channels)

the use of ALL-CAPS can also be considered spam (Only use capital letters to add emphasis to key words in a sentence)

the use of flashing/blinking colors can also be considered spam (don't go nuts with colors & avoid flashing/blinking colors if possible)
Causing the above types of spam can be grounds for a silence or even a period spent in Hell or possibly worse, depending on the method used and how many times an Immortal has had to address this issue with you.