Reducing Unwanted Energy Transfers

To reduce unwanted energy transfers the most common types are insulation and lubrication. 

For example, when you want to keep a drink cold in a cooler box with ice, you are insulating the box to keep it cold.
This is the same as closing all the windows in your house to trap heat or cold air so that it doesn't escape through convection. Then we have to reduce the heat loss from solids which is conduction, to combat the loss of heat houses are built with thick walls to keep the heat trapped. But certain walls have gaps between the outer and inner walls, which is a space that can also lose heat, so we put an insulator (usually foam) between the outer and inner walls of the house to trap the heat in.
Windows are also important to help reduce the amount of heat or energy lost, and the amount of glazing on the window pane.

Now about lubrication, which is used in all kinds of machinery, typically oils or greases, from wheels to ball bearings, to doors moving, if it moves normally it's pretty oily to the touch and was lubed to make it move smoother.
This also helps with reducing heat conduction which