This statement does noting.
The NOP statement will create 1 NOP assembly instruction. A NOP takes 1 machine cycle and can be used to create a small delay.
For example, at a processor clock of 1 MHz, one NOP will take exact 1 uS to execute.
You can use the ASM NOP by using : ! NOP in your code, but since using NOP is popular amongst many programmers, we introduced it as a BASCOM BASIC statement as well.