unit test vs integration test vs system test vs acceptance tests


what are differences between
unit test vs integration test vs system test vs acceptance tests
please advise
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Paul SauvéRetiredCommented:
here is a simple explanation:

a system is generally made up of modules and modules made up of functions

as an example, an accounting system would, among others, have modules for accounts receivable & accounts payable

accounts receivable would have a billing function and a function for posting payments received from the billing function to the ledger

accounts payable would have functions for entering received billing for materials and a function for posting paid bills to the ledger

unit testing: when you create one of the units, you have to test that the code works correctly by itself, without respect to the rest of the system

integration test is testing the unit within the associated module so it functions correctly with respect to the module

system test is testing that the entire system works correctly when all the modules have been tested

the above tests are usually carried out by those working on the project

acceptance tests are the tests done by the users who funded the project to make sure that the system meets their original requirements

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Paul SauvéRetiredCommented:
this answer seems correct to me!
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Web Development

From novice to tech pro — start learning today.