How to look up a symbol? Escape character in latex in the itemize environment, how do i use the ampersand symbol & without latex trying to use it as a command? Q&a for users of tex, latex, context, and related typesetting systems

All this just means that they are not promising that $$ will always work. Sometimes the symbol := is used to denote a definition. For example, x:=y+z means that x is defined to be y+z. When using latex, can i just use $:=$, or do i need to do something special?