“OpenMRS 1.9.x” is the previous version of “Platform 1.10.x” and then “Platform 1.11.x” (the current version). The next version released later this year will be “Platform 2.0”. Platform is a basic installation of the OpenMRS API and web tools on which someone needs to customize to build various types of systems.
“OpenMRS 2” (not to be confused with Platform 2) is a new product that is built on top of Platform 1.10 or in the new version about to be released, on top of Platform 1.11. OpenMRS 2 is designed to be an out-of-the-box “distribution” ready to support health care needs.
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