A key fob is a small accessory that serves as a key chain with additional function, for example providing an LED display.

Some people call them “keychains”. Others use the term “car remotes”, because traditionally many car remotes control features of the vehicle when carrying the remote on your belt. The corded version of these were also called a “lanyard”. In addition, some people call them “man-purses” or “alarm buttons.” Other names include purse fobs and ballpoint pens and occasionally wristbands. Women’s size wristwatch can be considered small enough to fit in most men’s pocket so they are often used instead of wearing watches on one’s arm (such as when playing basketball).

A key fob (also known as an auto remote, wireless entry device, or keyless entry remote) is a small electronic device used to unlock or lock vehicle doors. The typical key fob has buttons on both sides of the face; one locks and unlocks the vehicle’s doors while the other triggers its alarm system. Some early designs of key fobs had a metal key at the bottom capable of operating a lock.

The purpose of a remote is to allow the vehicle operator to have both hands available on the steering wheel while locking or unlocking doors or activating other systems, thereby reducing the risk of theft by enabling the vehicle operator to keep his or her foot on the brake pedal and the vehicle in gear.

If a molecule has the same dipole moment as water, then it is polar.

Hydrogen chloride (HCl) and methane (CH4) are both polar molecules because they have the same dipole moment as water.

But sulfur dioxide (SO2), nitrogen dioxide (NO2), or nitric oxide (N2O) are nonpolar molecules even though they form hydrogen bonds with individual water molecules since their dipole moments cancel out each other. A molecule can also have a permanent static charge that electrically polarizes its surroundings; if such is the case, then it will be considered to be a polar molecule.