An Office 365 reseller is a company who sells products or services to other organizations.
They act as an agent for the software vendor, but they may also offer additional support such as installation and configuration of their products. In the case of Office 365 resellers, these individuals or companies are authorized by Microsoft to purchase and sell Office 365 licenses to other businesses.
Microsoft renamed the Microsoft Office 365 software to Microsoft 365 in October 2022.