Not talking engines, transmissions, differentials, etc. just really more run of the mill stuff... hinges, toys, tools, plastic stuff, etc. Is there a best practice rule of thumb for what to use when? Start with this: silicone vs hydrocarbon? My take is silicones are for plastic, and for low/no load use only. Bearings and whatnot have to be severely derated if using a silicone lube. Silicone can be used for metal to metal, but it is less advisable, Now, what about grease vs oil vs penetrating oil? Some penetrant are really intended to creep, some seem more multifunction. But when do you change from a very light penetrant to an oil to a grease in day to day use? Based upon load? Geometry/orientation? Etc? Could probably ask the same for dry lube. Is it more a matter of materials (like rubber on rubber when you don't want it wet or smeary), or is it more in case of fine dirt and grit, or what? Ive never really seen a concise and direct mapping of products to uses. I'm sure many products would claim utility to many applications, but what is best practice and for what materials?