QA is like you aware the risk of the application or system 
and you made the all the necessary things to face the risk.
QC is like you did things after the crash or after facing 
that risks for the application or system.

QA is like to be maitained standerds and awareness of 
risks, they will make sure which one will be better to 
follow.
QC is like to be make sure quality , sacrigate the bad 
process i mean remove the unqualitative product

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Quality Assurance
Preventing problems
Prepare Standards and Guidelines
Review the reports
Prepare the test plans
Verification

Quality Control
Identify problems
Implement Standards and Guidelines
Prepare the reports
Implement the test plans
Validation

quality assurence
it concentrate on the process of the product.
it is defect prevention method. 
it checeks to follow the quality standars or not
it is done thorughout the lifecycle.
quality control
 it concentrate only specific products
it is generallay done after the product is bulit.
it is defect-detection and correction method.

Hi friends,

QA- Quality Assurance.
It is process oriented.
It suggest improvement or changes in process.
Out put of QC.is input to QA.
Verification is related to QA.
It is preventive type.
Inspection is example of QA.

QC-Quality Controll.
It is product oriented.It suggest improvement or changes in 
product.
It follow all norms and rules defined by QA.
Validation is example of QC.
It is detective type.
Testing is example of QC.

BYE.
If I m wrong pls correct me on
sham_sap@rediffmail.com