Cloud vs on-premise
Cloud software runs on remote servers you access over the internet. On-premise software runs on a server installed at your practice.
On-premise, or server-installed, software runs on hardware in your building. It works without internet and you control the machine, but you also maintain it, back it up, and replace it when it ages. Older veterinary systems like AVImark and ImproMed are typically on-premise.
Cloud software runs on remote servers and you reach it through a browser. There is no hardware to maintain, and you get updates automatically, but you depend on a connection and, with closed systems, on the vendor's control of your data.
Open source gives you a third path. With OpenVPM you can self-host, either on your own hardware or your own cloud account, or use managed hosting. You are not forced to choose between control and convenience.
See how OpenVPM does it
OpenVPM is the open-source veterinary PIMS. Free to self-host, with an open API and your data always exportable. The demo is live, no signup.