SAP ECC and R/3
SAP ECC stands for SAP ERP Central Component.
The term "SAP ECC" is wrongly used as "ERP Core Component" or "Enterprise Core Component" accross various website on the internet.
Its predecessors is SAP R/3 Enterprise.
SAP ECC and SAP R/3 are online transaction processing (OLTP) systems.
OLTP systems satisfy day-to-day transactional needs of many users.
There are a number of modules within each of these prodcuts.
In case of SAP R/3 these modules were called submodules.
In ECC these modules are called subcomponents.
Examples of these modules are finance, logistics, human resource management, customer service, and quite a few others.