In general, the rules for naming fields (data elements in a table) and variables (data elements within the working storage of an object) are the same, and we will discuss them on that basis. Information on this can be found in the released C/AL Coding Guidelines at https://community.dynamics.com/nav/w/designpatterns/156.cal-coding-guidelines, including a How do I video.
Variables in Business Central can either be global (with a scope across the breadth of an object) or local (with a scope only within a single function). Variable names should be unique within the sphere of their scope.
Uniqueness includes not duplicating reserved words or system variables. Refer to the AL Reserved Words list in the Developer and IT pro help for more information.
