Metal is a thermal conductor and Wood is a thermal insulator. When you touch the metal the energy transfers rapidly to the metal, making it colder. When you touch the wood the energy transfers very slowly from your hand to the wood, this is why metal feels colder t touch than wood kept in a cold place.

At night, the land cools down much quicker than do the waters of the ocean. As the land becomes cooler, so does the air above it. This results in the air becoming denser forming a high pressure, causing winds to blow outward towards the sea this is known as a land breeze.

Thus, during the day we often see sea breezes while in the evening VC land breezes in coastal regions. 

A vacuum flask consists of three vessels. One is the outer casing which simply holds the inner, double-walled glass vessel which is brightly silvered, both inside and outside. This inside silver inning reflects heat into the hot liquid inside (or prevents heat from entering into a cold liquid). The outer wall is also silvered on both sides for the same reason.

Between the two walls which are sealed together at the top and bottom is a vacuum (a very low pressure) that has very few particles (molecules) through which leader conduction convection will easily take place. (These forms of heat transfer need particles by which they will transfer the heat). However, radiated heat bill passes through a vacuum this is where the silver surface comes into use.

In deserts, sand has low specific heat which is why it will soon get heated or cold. Hence desert nights are colder whereas the days are very hot.