What is RMM? (remote monitoring and management)
RMM stands for remote monitoring and management: software that puts an agent on every computer a team looks after, so all of them can be watched and fixed from one dashboard. The agent reports health and inventory, raises alerts, and gives the technician remote desktop, a terminal and script execution without visiting the machine.
What an RMM actually does
Four jobs, roughly: it tells you what you have (hardware and software inventory), tells you when something is wrong (monitoring and alerts), lets you act on it remotely (remote desktop, terminal, scripts), and does routine work automatically (patching, maintenance scripts). The agent connects outward to the vendor's servers, which is what makes machines behind home routers and client firewalls reachable without any network changes.
Who uses one
MSPs run RMMs to look after many clients' machines at once, and internal IT teams use the same tooling for their own fleet. The alternative is per-machine remote access tools plus spreadsheets, which stops scaling somewhere around the second dozen machines.
Related terms: PSA, patch management, EDR.