Hexadecimal

Hexadecimal is the numbering system commonly used in ROM hacking. It uses 16 different digits, as opposed to the 10 that we are more familiar with.

It uses the digits 0-9, and then the letters A-F, with F = 15 and 10 = 16.

When bringing up hex notation on SMW Central, it's helpful to precede your hex number with "0x" to avoid confusion; this is the notation most commonly used throughout the world of hacking and computing. .ASM files use "$" to indicate a hex number. If you're making a custom layout on SMWC and want to change the colors of your text, the "#" sign is used to begin a hex number in HTML and CSS. Examples

   "Editing the title screen is a two-part process; you have to go into Lunar Magic's Title Screen Editor within the Overworld Editor, then edit Level 0xC7."
   "A fatal exception has occurred at 0x358925BA294A3."
   LDA $FFFFFF STA $000000 RTS
   .smwikithingy {color: #FF0000;} 

Categories

In the world of ASM hacking and programming, the following categories are used when dealing with hexadecimal numbers:

   A one or two digit hexadecimal number is called a byte.
   A three or four digit hexadecimal number is called a word.
   A five or six digit hexadecimal number is called a long.
   A seven or eight digit hexadecimal number is called a dword. 

Other information

Upper-cased hexadecimal numbers which contains digits A-F are generally easier to read than lower-cased A-F.