ppsc is an organization who is responsible to select civil servents in different govt departments. such as education, medical,police, excise, labour, finance,and many more
The ppsc is vested with the responsibility of making direct recruitment for various posts under the Government of Punjab.

on other hand pms is the kind of a test under which top list post of province are filled by an exam called provincial mangment services
the following seats are filled under this exam
tehsildar
ddor
depty suprintendent of jailer
excise and taxation office
section officer
etc

so ppsc is a commission or institute
while
pms is the name of an examination

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