Engine oil is a liquid lubricating oil, which is easy to use, but it is easy to evaporate and dry up, and is generally used for daily lubrication and maintenance. Wisdom. Butter is the old lubricating oil of lubricating channel, which is inconvenient to use, but it works for a long time and is generally used for long-term maintenance or overhaul. Fans in computers usually don't refuel-unless you use an old fan! In addition, these two oils are petroleum products and a mixture of various hydrocarbons. The difference lies in the melting point. The edible butter mentioned upstairs can't be used for lubrication!