SAP ECC is the core component within the SAP's Business Suite (a collection of applications including SAP CRM, SAP SCM and others, alongside the ECC component). SAP ECC contains different, but integrated, functionality within its "modules" e.g. Finance module, HR module, Warehouse Management etc. all within the ECC). The combined complexity of the Business Suite, along with newer in-cloud competitors, has in recent years led SAP to invest heavily in simplification and massively improved system response times, culminating in the announcement of the S/4 Simple Suite in February 2015. S/4 has a single tenant architecture and is being built upon SAP's in-memory database technology stack (HANA) and will be available in a choice of in-cloud and on-premises deployment. The classic three-tier and database-agnostic architecture of R/3 is replaced with a two-tier architecture.