Variables

[WHIPENIE4]

Ok im slowly learning how to script , im kinda stuck on varibles... when do you use them??

In the example they use in npcprogramming
myvar = 1;
if (myvar==1) {..........}

So if the varible ='s 1 then the command in {.....} will be executed...... but lets say
the command in the {...} was messageHello;
then why not just put
If (playertouchsme) messageHello;
???
Or 'playerenters'

[edit]Also what do these symbols mean
>,<,>=,<=,==,!= , or when do you use them?[/edit]