How Horsepower Works

The word "horsepower" is constantly mentioned regarding car and industrial engines. This edition of How Stuff Works defines the term, and explains how to measure it.DefinitionThe term horsepower was coined by engineer James Watt, who is most famous for his work on improving the performance of steam engines.

How Computer Memory Works

Although memory is technically any form of electronic storage, it is used most often to identify fast, temporary forms of storage. If a computer's CPU had to constantly access the hard drive to retrieve every piece of data it needs, it would operate very slowly. When the information is kept in memory, the CPU can access it much more quickly.

How Email Works

An e-mail message is a simple piece of text sent to a recipient. E-mail messages tend to be text, although the ability to add attachments has become increasingly important. To look at e-mail messages, you use an e-mail client. Many people use well-known, stand-alone clients, such as Microsoft Outlook, Outlook Express, Eudora, or Pegasus.

How Ethernet Works

Ethernet is a local area network (LAN) technology with networks traditionally operating within a single building, connecting devices in close proximity. At most, Ethernet devices should have only a few hundred yards of cable between them. For two devices on a network to successfully communicate, they must both understand the same protocol.

How Encryption Works

Encryption is the process of encoding information in such a way that only the computer with the key can decode it. Most computer encryption systems are either symmetric-key encryption or public-key encryption Symmetric-key encryption is a secret code that each of the two computers must know in order to decode the information.

How Computer Viruses Work

Computer viruses are called viruses because they share some of the traits of biological viruses. A computer virus passes from computer to computer like a biological virus passes from person to person.A biological virus is a fragment of DNA inside a protective jacket. Unlike a cell, a virus has no way to do anything or to reproduce by itself.

How Serial Ports Work

The serial port has been an integral part of most computers for more than 20 years. Serial ports provide a standard connector and protocol to let you attach devices, such as modems, to your computer.All computer operating systems in use today support serial ports. Parallel ports are a more recent invention and are much faster than serial ports.

How Parallel Ports Work

The parallel port is the interface most used for printers. They are also used to connect a PC to scanners, CD-writers, external hard drives, Zip removable drives, network adapters, and tape backup drives.Parallel port basicsIBM originally developed parallel ports to connect PCs to Centronics printers.

How Bearings Work

The bearing makes many of the machines we use every day possible. Without bearings we would constantly be replacing parts that wear out from friction.Objects roll more easily than they slide. The wheels on your car are like big bearings. If you had something like skis instead of wheels, your car would be much more difficult to push down the road.

How Bluetooth Short-range Radio Systems Work

Bluetooth is a new standard developed by a group of electronics manufacturers that will allow certain electronic equipment to make its own connections, without wires, cables, or any direct action from a user. Bluetooth is intended to be a standard that works at two levels:Bluetooth is intended to get around the problems that come with both infrared and cable synchronizing systems.

How Work, Power and Energy Works

What is work?Work is the application of force over a distance, with one catch — the distance only counts if it is in the direction of the force you apply. Lifting a weight from the floor and putting it on a shelf is work. The force is equal to the weight of the object, and the distance is equal to the height of the shelf.

How TorqueWorks

Torque is the force that tends to turn or rotate things. You generate a torque any time you apply a force using a wrench, such as tightening the lug nuts on your wheels. When you use a wrench, you apply a force to the handle. This force creates a torque on the lug nut, which turns the lug nut. English units of torque are pound-inches (lb-in.

How Mass and ForceWork

Terms such as mass, force, torque, work, power, and energy are frequently encountered around the industrial plant. This month's column, along with the next two, will take a look at what these terms mean and "how they work." What is mass? Generally, mass is defined as the measure of how much matter an object or body contains — in other words, the total number of subatomic particles (elect...

How Relays Work

A relay is a simple electromechanical switch made up of an electromagnet and set of contacts. As simple as they are, however, relays are found hidden in all sorts of complicated products. In fact, some of the first computers ever built used relays to implement Boolean gates. Construction Relays consist of four parts: Electromagnet Armature that can be attracted by the electromagnet Spring Se...

How the power distribution grid works

Electrical power travels from the power plant to the industrial plant through the power distribution grid. All commercial electrical generators of any size generate three-phase ac.