In assembly language, labels are used to represent locations within a program. They can be used as the target of any branch instruction and are often used to identify the start of a subroutine or the beginning of a loop. Labels consist of up to fourteen characters with a terminating colon (15 total). The first character must be alpha, but all subsequent characters can be either alpha or numeric (digits). Label names cannot include spaces or other special characters such as hyphens, underscores, etc., and they must be unique within the program code. For instance, if you have two labels, both named "START_LOOP", only one will remain after compilation, and the other will produce an error when compiling your code. In addition, some systems may limit label names even further by requiring them to begin with an underscore (_). It's important to choose meaningful labels so that it's easier for other developers who read your code to understand what the code is doing. This makes it easier for someone else (or yourself) down the line when they need to make changes or debug errors in your code. For example, instead of using "LABEL1" as your label name, try using something like "MAIN_LOOP". This way, it's clear what this label is doing without having to read through all of its associated code.