The Q.A team role is to maintain the quality , has to be
assured in each and every phase of the development phase.
The Q.A team audits the work of the various development team
to ensure that the process definitions are followed strictly.

Quality Assurance (QA)Process of Consists of planning, 
coordinating and other strategic activities associated with 
measuring product quality against external requirements and 
specifications (process-related activities).Quality 
Assurance helps establish processes. Quality Assurance sets 
up measurement programs to evaluate processes.Quality 
Assurance identifies weaknesses in processes and improves 
them. Quality Assurance is a management responsibility, 
frequently performed by a staff function. Quality Assurance 
is concerned with all of the products that will ever be 
produced by a process. Quality Assurance personnel should 
not ever perform Quality Control unless it is to validate 
Quality Control. Quality assurance is a system of 
management activities. Quality assurance  (QA) is 
preventive process. Quality assurance  (QA) applies to the 
entire life cycle

quality assurence is the preventive macanism and are 
responcible for maintain quality of software/product.the 
purpose of QA is to enforce and make the standard and make 
sure that these company standard is followed by company or 
not.s/w testing is the detection and QA is the preventing 
Process.