An EPICS installation typically consists of multiple software modules.
EPICS Base will always be one of them. Base and additional modules that provide libraries or tools are often referred to as Support Modules, while the modules that produce your control system are often called IOC Application Modules.
EPICS Base and the Support Modules are usually common and shared between the IOC Applications of an installation. You can consider a stable and tested set of Base and Support Modules a release of your development environment.
As Support Modules are shared, have a longer life cycle and are held more stable than the IOC Applications that use them, it is a good idea to keep the Support Modules and IOC Applications separate.
This section will mostly cover installing EPICS Base and Support Modules. IOC Applications are too specific to be covered by general documentation.
The traditional way to install EPICS is by compiling from sources.
While the specific instructions differ between Operating Systems on your host, the general steps are always the same:
Download, configure and install EPICS Base
Download, configure and install Support Modules
Create your IOC Application
Which version should I chose?
Please use new versions.
Unless you have specific reasons to use an older version, using the current release will make sure you have all the features and all the bug fixes. Using current versions for all modules in your set of Support Modules minimizes issues that may show up because of incompatibilities.