OpenShift allows you to create, deploy, and manage applications within the cloud. It provides disk space, CPU resources, memory, and network connectivity. You can choose from a range of web cartridges, including Tomcat, WildFly, Jenkins, and many more. You can also plug in database cartridges, such as MySQL. Depending on the type of application you are building, you also have access to a template filesystem layout for that type (for example, PHP, WSGI, and Rack/Rails). OpenShift also generates a limited DNS for you.
To get started with OpenShift Online, the first thing you need to do is create an account. Go to OpenShift's home page at https://www.openshift.com/, and select SIGN UP. Complete the online registration and verify your e-mail address.