OpenShift Online 2 will cease operation on 31 December 2017. Questions about OpenShift Online 3 should be tagged openshift-online-3.
OpenShift Online is Red Hat's Platform as a Service (PaaS), a cloud application development and hosting platform that automates the provisioning, management, and scaling of applications so that you can focus on writing code for your business, startup, or next big idea.
Check out the Getting Started page to get up and running quickly, see the Developer Portal for more in-depth topics, and visit the Help Center for even more resources and guidance.