Definition
The process of confirming that a system or component complies with its specified requirements and is acceptable for operational use.
[Source: BCS]
Comment
Certification can show that a system or component has been through a particular process.
A system will not be made to work by simply going through a certification process. People often do not understand what certification is and become confused.
On many programmes and large projects, testing will take up a significant portion of the budget. But it will receive less management attention than an activity of this size warrants.