the way I understand tallow is beef fat Lard is pork fat I don’t see any soaps made with lard. Or is lard and tallow used interchangeably. Is there feel or technical difference between lard, tallow.
Theoretically any rendered animal fat can be referred to as tallow but usually it is only used for rendered fats that are hard (beef/sheep) rather than soft(pork/chicken). Lard used to be a common ingredient in shaving soaps/creams in the 20s-30s but I don't know of any brands that use it curently. As far as the technical difference in soaps made from different "tallows" check this LINK
This general subject has come up recently, so I recalled doing some reading. Understand that unlike Chris @americanshamrock who has soap making experience, I'm only a user. The fatty acid, also called oil, fat, lard, or tallow used to make soap determines the properties of the finished product. Each source may vary in percentages of the following described because these are biological products that are affected by weather, life cycle of the source, care and handling of the raw product prior to making the soap, and the soap making process it's self. The properties of common fatty acids for soapmaking are (7): Lauric Acid: Hard bar, excellent cleansing, lots of fluffy lather, can be drying to skin. Linoleic Acid: Conditioning, silky feel. Myristic acid: Hard bar, cleansing, fluffy lather Oleic acid: Conditioning, slippery feel, stingy lather, kind to skin. Palmitic acid: Hard bar, cleansing, stable lather. Ricinoleic acid: Softer bar, conditioning, moisturizing, lots of fluffy stable lather, kind to skin Stearic acid: Hard, long lasting bar, stable lather If that's not a brain full of information, here's more reading about Fatty Acid Analysis of Grass-fed and Grain-fed Beef Tallow & Determination of fatty acid composition of pork fat