holy s**t so many different answers there lol here we go.......
MK2 ph1
MK2 ph2
MK2 Ph3
MK2 ph4 (aka Campus)
The differences....
MK2 ph1 was the original MK2 then in 2001 they brought out the ph2, full different interior, different front end, different side strips, wheels, rear lights etc, same engines were availible (1.2 8v, 1.2 16v, 1.4 16v and 1.6 16v) along with the adition of the 1.5 DCi to replace the older 1.9dti
then in early 2004 they were facelifted to ph3 starting with 53 plates (some 53 plates are some are not!) they got a new front bumper, new grill, headlights stayed the same apart from grey backs instead of black and the rear spoilers were colour coded as standard, inside the dials were changed giving a bigger screen for the trip computer and the seats were given a new design the wheels were also changed to a 15" version of the 172 wheels, ph3 models also did not have a sunroof (about time!!) models without fog lights came with a ph2 front bumper instead of the ph3 one.
ph4 then came along with the release of the mk3 clio, these were badged as either a clio campus or a clio campus sport (although their was clio campus models in ph3 guise to begin with) ph4 featured again a new front bumper, the badges on the bump strips were deleted of any text (16v, dci etc) and the rear bumper was changed to allow the number plate to be fitted to the bumper, the boot was then smoothed where the plate usually goes.
hope this helps ive probably missed out a load of bits n bobs but that gives you the general idea.
EDIT: in 2004 the 1.2 16v engine was revised with a new inlet manifold, throttle body and ecu along with a few other bits n bobs to make it a bit more economical and get rid of some common faults.
no "new" power figures were ever released but in my experiance you get a bit more torque from the shorter inlet tract, sound a bit better and thank god they got rid of the flexi joint on the cat that the older style engine had as it was a pain in the arse i kept bursting them catching my cat lol
and for reference the OP's car is a mk2 ph2 Dynamique as stated above somewhere!