Dear fellow friends, I recently purchase a campagnolo record rear hub with 28 holes believe to be from the 70's but notice that I could not fix in my shimano 600 5 speed freewheel onto the hub.
Can I be enligtened on how many types of threading does Hub ,headset and bottom bracket have? I m confused about it.
If yes , how do I identify wat type of threading my hub r having?

HK - All of the campy hubs that I have around have the threading in small letters around the flat in front of the driveside flange, just before the threads...from Sheldon's site

Type Thread Specification Equivalent
I.S.O. 1.375" x 24 tpi 34.92 x 1.048 mm
British 1.370" x 24 tpi 34.80 x 1.058 mm
French 34.7 x 1 mm 1.366" x 25.4 tpi
Italian 35 mm x 24 tpi 1.378" x 1.058 mm
Metric BMX 30 mm x 1 mm 1.181" x 25.4 tpi

I think that if you spent some time looking you could find some additional sizes, but this list takes care of most of the possibilities.

I check & confirm having italian threading,does that mean i hav to use a freewheel with italian threading?
& how do i identify wat freewheel threading use?

If the freewheel looks and feels as though it should go on, but starts to bind up as your tighten it, you may have an English/ISO-threaded freewheel and an Italian-threaded hub. The sharpness of the threads differs, so switching between English and Italian freewheels gradually erodes and weakens the hub's threads.

Wat thread normally does vintage shimano 5-speedfreewheel normally comes with as there is no indication on the freewheel itself.
Any advise?

Unless otherwise noted, most Japanese parts are English spec, at least in the US.