Ref: KBN123286 Software testing life comprises various activities with specific goals. Organizations may tweak these to align with their corporate philosophy, but the basic essence remains the same.
In the waterfall model, the activities are performed in phases as shown in the Waterfall diagram below, whereas in the Agile model, all these activities are performed in every release, as shown in the following agile diagram below click the link to see the agile diagram. : www.webomates.com/blog/software-testing/software-testing-life-cycle/
More details: Software Testing Life