PO is uniformed. SPO leh??? Then non-uniformed de mostly is need higher qualifications??? Paiseh ahh abit confused about the SPF structure...
Sry for bad english.
police officer = any normal rank or SI (station inspector)... equivalent to army enlistee/specialist/sergeant/warrant officer.
SPO = senior police officer (Regulars are degree holders only or NSF/NSmen with min dip/A) ... means go through 9 months training and commissioned with sword as Inspectors....
non uniformed....no such thing la... everyone got uniformed. plainclothes is just for IO (investigation officer/CID) etc who need to be not recognised as police so easily. But they still have rank/uniform, but normally don't wear. They are also either normal police officers or Senior police officer...normal ranks like the rest.