Traceability matrix is a table type document that is used in the development of software application to trace requirements. It can be used for both forward (from Requirements to Design or Coding) and backward (from Coding to Requirements) tracing. It is also known as Requirement Traceability Matrix (RTM).
Generally, this is like a worksheet document, which contains a table, but there are also many user-defined templates for traceability matrix. Each requirement in the traceability matrix is connected with its respective test case so that, tests can be carried out sequentially according to specific requirements.
A table is given below as an example so you can understand the formate of traceability matrix:
We can see in the table there are three columns and four rows used to denote Business Requirement, Technical Requirement and Test Case ID.
Suppose that any user requires registration, and B1 is the identification of this requirement, so the tester needs to select B1 and he can use the code of T12 to develop registration function. Testing of this function can be done by using test case ID 1.
Goals of Traceability Matrix