Fish model explains the mapping between different stages of development and testing.

Phase 1

Information gathering takes place and here the BRS document is prepared.

Phase 2 

Analysis takes place:

During this phase, development people prepare SRS document which is a combination of functional requirement specification and system requirement specification. During this phase, testing people are going for reviews.

Phase-3 

Design phase:

Here HLD and LLD high level design document and low level design documents are prepared by development team. Here, the testing people are going for prototype reviews.

Phase-4 

coding phase:

White box testers start coding and white box testing is being conducted by testing team.

Phase-5

testing phase:

White box testing takes place by the black box test engineers.

Phase-6 

release and maintenance.