Difference between Regulated and Stabilised power supplies

[chrisc]

On Ali Express there are many hundreds of ads for power supplies

If one leaves out switched mode PSU, which I believe are intrinsically noisy and look for Linear PSUs, then the following criteria are presented

Regulated
Stabliised
Pressure regulated
Over voltage regulated

Then some specify the residual AC voltage. On some it is 25µV, others it is 1µV

Is there a substantial difference, or is it marketing hype?

There can be a substantial price difference