Originally posted by bigted Before I became a point and shoot victim I had a 35mm Praktica PLC2. ...
The smaller lens is a Pentacon electric 1.8/50. Attached is a filter (?) that says B-W 49ES 010 1X.
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The larger lens I understand is a telephoto lens (although I am not sure exactly what is the difference between a telephoto and zoom). It has no filter. On the lens it has skyline 1:2.8 f = 135mm and no. 2235046 (serial no????).
The Praktica PLC2 was/is an M42 screwmount camera. Your Kr is a PK (Pentax bayonet-mount camera). M42 lenses like yours can be used on your Kr with just a simple M42-PK adapter; the Official Pentax adapter may cost US$25-40 depending on how well you search eBay. We have LOTS of information here on using such lenses with your camera.
The Pentacon Electric 50/1.8 is a later version of the Meyer Oreston 50/1.8, a very popular and highly-regarded prime (fixed focal length) lens. The filter is not important; if the lens has been stored in a dark moist place, fungus may grow under the filter. It's best to remove it.
The Skyline lens is, as Adam said, a telephoto prime lens. A zoom may be wide or standard or telephoto, but it covers a range of focal lengths. Prime lenses are generally sharper and faster (wider maximum aperture) than zooms. Your Skyline tele's serial number starts with 22, so it was likely make by Kino Industries aka Kiron. Kiron is a highly-regarded 3rd-party lensmaker and your 135/2.8 is probably quite a decent lens.
Welcome to the dSLR world! Welcome to Pentax! Don't hesitate to ask any questions here. The only dumb questions are those that aren't asked. Have fun!