* Res. is a common abbreviation for "Resource"
* Rsc. is another less common but still used abbreviation for "Resource"
* Rs. is an abbreviation for "Resources" (plural)
* R can also be used in specific contexts, especially when referring to a specific resource or within a system where "R" is established as the abbreviation for "Resource."
The best abbreviation to use will depend on the specific situation and audience.