What is a variable or function name length limit? The limit specifies the number of characters which are significant in a variable or function name (often also refered to as a label). Some compilers restrict the significance to a number like 8, 12, 16, 20 or 32. This meens that if two variables are used in a system which only allows 8 significant characters, these labels must be different within the first N characters, otherwise the compiler will confuse them as the same variable. e.g. on a compiler with a restriction of 8 significant characters the labels: heigh_level_count heigh_water_mark would be seen as different, however heigh_water_mark_2 would be confused with heigh_water_mark which would lead to the compiler generating incorrect code XCSB has no length restriction on variable and function name. This is very useful, not only does it avoid silly errors, it also allows labels to be as descriptive as the programmer wants, and allows the programmer to prefix labels with meaningful tags (e.g. the name of the module to which the function or variable belongs).