Top 10 Appliances We Can't Live Without

1: The Clock

Whether you prefer digital or analog, there's a good chance that a wall of your classroom, the desk in your office or a bank you passed on your ride to work or school sported a clock. If that isn't enough, there's the clock in the family car, and all of the ones on the DVD players, VHS players, cable or satellite boxes, televisions, microwaves, coffee makers and ovens. The time seems to be everywhere, but that wasn't always the case.

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Clocks can be found just about everywhere.

The first clock was most likely a stick partly buried in the ground. As the sun made its circuit across the sky, the shadow cast by the stick moved in measurable increments. This was a rudimentary sundial; a smart, if limited, way to tell the time. Accuracy was the real problem when it came to early man's attempt to lock down short-time measurement. The sun was a great indicator, but the system didn't work at night or when it was cloudy outside. Another problem was that the length of the day changed throughout the year, changing whatever incremental measurement was set to mark the time.

In the 2^nd century, Ptolemy, a Greek astronomer, deduced that placing a slanted object parallel to the Earth's axis would provide a consistent incremental measurement regardless of the season [source: Behar]. This led to standardized time measurement, solving one problem. The second problem, telling time when the sun wasn't shining, inspired a number of ingenious solutions. Water clocks used dripping water, leaving a small opening in a container to mark the passage of time. Candles were also widely used because they burned at a consistent rate when there was no breeze. Romantic methods like hourglasses were also widely employed, but it wasn't until around the beginning of the 14^th century that a new, reliable method came on the scene: the mechanical clock.

The Birth of the Alarm Clock Ever wondered who’s to blame for that alarm clock blaring in your ear every morning? Well, you can thank the Greeks. Around 250 B.C., a modified water clock whistled when the clock’s water rose to a certain level [source: Bellis].

­No one knows who invented it, but this remarkable device used an oscillating escapement to control the movement of the clock mechanism [source: Eveything2.org]. This was a pretty stable method of short-time measurement, and it revolutionized the way man related to the passage of time. Now, people could begin setting appointments and reliably keeping them. Precise planning, like that of many religious observances, could be closely scheduled. The world was beginning to change. A faster pace was possible because it was easier to organize activities. Man was on the road to three-minute eggs, stopwatches and power lunches.

Now that we can synchronize our watches, let's proceed to the next section where we'll explore the wonders of the toilet.
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2: The Toilet

The History of Bathroom Tissue In 1880, the British Perforated Paper Company manufactured the first paper used especially for personal hygiene. Before bathroom tissue (also known as toilet paper), people used a variety of useful and sometimes unusual items. When paper was scarce, leaves, sand and sticks were usually plentiful. People used items that were nearby and disposable, even resorting to stones and shells when they couldn’t find anything better. Later, reusable sponges were sometimes used too. After paper became more commonplace in the late 15th century, recycling was the order of the day. Privies, water closets and chamber pots were equipped with old letters, newspapers and old paper bags.

Although attempts at developing a plumbing system can be traced to Mesopotamia around 2,500 B.C., it was the Romans who implemented a broad plumbing plan [source: Behar]. Under Roman supervision, outhouses were strategically placed over a network of sewers equipped with running water. It was a great idea, but it didn't catch on very quickly. By the Middle Ages, Europeans were still pitching waste out of their windows, and the humble chamber pot was a staple in every home. The stench in London's streets from the lack of sanitation was awful, and after a devastating cholera epidemic, a comprehensive system for sewage disposal became a priority [Source: Behar].
This roughly coincided with the manufacture and distribution of a new luxury item, the flush toilet. The indoor facility that housed this wondrous device was called a water closet. Although aborted attempts at indoor waste disposal have been discovered as far back as 2,500 B.C., it wasn't until Sir John Harrington created an inspired water closet design in the 16^th century that indoor plumbing became a practical reality. An upgraded version consisted of a bowl with a hole at the bottom that was fitted with a valve. Water was fed to the bowl from a cistern, and gravity was used to flush the waste after use [source: Castleden].

­Thomas Twyford is the man to thank for the manufacture and distribution of what would become the modern toilet. He took the water closet concept, refined it and mass-produced it. By 1885, the clumsy and unhygienic water closet had morphed into a sleek all-china closet. This was a clean and efficient precursor to the modern commode.

Now, we'll move from the bathroom to the kitchen and look at the refrigerator.
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3: The Refrigerator

The next time you make your midnight foray to the fridge for a piece of pie or a leftover burrito, consider what life would be like without that big cold box. You wouldn't have ice for your drink, and you wouldn't be to keep food fresh. Many of the staples you enjoy like eggs, milk, cheese, meat and butter would have to be purchased in small quantities or not at all. Expand this to the broader landscape, and much of the variety you see in your local market would be impossible to ship, store and sell before it spoiled. You might even have to resort to growing some food yourself to insure that you had a regular supply.

The Ice Trade In the early 1900s, an American businessman, Frederic Tudor, made his fortune by shipping ice around the world. He outfitted ships with special insulation, packed them with blocks of ice and delivered them to the Caribbean and beyond, making his place in history as the first Mr. Freeze.

­The father of the modern refrigerator, Carl von Linden, didn't build a cold box; he developed a process that changed a gas into a liquid [source: Behar]. This process had an interesting side effect: it absorbed heat. Refrigerators work by using a system of coils filled with this liquid coolant to transfer heat out of the confines of the refrigerator's insulated compartment.

The first refrigerator built for the purpose of preserving food was made in 1911, and a practical, self-contained model was mass-produced by Frigidaire in 1923. Once production brought the price down, the market for refrigerators grew sharply. As an important refinement, a small freezer compartment used to make ice cubes was soon added. Iceboxes, or insulated boxes filled with ice to keep food cool, were used less and less, and the refrigerator became an essential appliance and a part of the modern home.

Now, we'll take a look at the next essential appliance on the list: the washing machine.

4: The Washing Machine

As long as people have been wearing clothes, they've had to come up with ways to clean them. If you lived a couple of thousand years ago, you'd be beating your clothes on a stone to get the stains out like the Romans did. They had special stone troughs for washing and used rendered animal fat as a crude form of soap. Fast forward a few hundred years, and the stone troughs were replaced with wooden boards for scrubbing. But the process was still slow and backbreaking, and the results were probably less than stellar.

Taking the Clothes off the Line ­Drying clothes when it rained used to be a big problem. Clotheslines were a great way to air-dry clothes when the sun was shining, but when it rained or the wind picked up, the outdoors was a hazardous spot for your wardrobe. Moving laundry day into the modern age meant more than just getting your clothes washed without a major workout; it meant drying them, too. Since its development early in the 20th century, the electric clothes dryer has been a popular appliance, working side by side with the washing machine as the dynamic duo of the laundry room.

­Things started to get interesting when agitators were developed. These paddles or dollies were suspended in a tub of water with the dirty clothes and then turned backward and forward manually. They still required muscle, but the process was similar in concept to the way we clean clothes today, agitating the water to release dirt from cloth fibers. In 1908, Alva J. Fisher introduced the modern washing machine. It was called the Thor, and it was the first washing machine with an electric motor [source: Castleden].

Modern washing machines use a two-drum system to clean clothes. The inner drum holds the clothes near the agitator, while the outer drum holds the water in the machine. When the washing cycle is complete, the inner drum spins, draining the water via hundreds of holes. In fact, during the final spin, a washing machine's inner drum can rotate at speeds approaching 80 mph (130 km/h) [source: Woodford].

Now that you don't have to spend two hours a day scrubbing dirty clothes, straining your back and ruining your manicure, you can chat with your friends and family on the telephone, the next appliance we can't live without.

5: The Telephone

The phone has gone from a fixture on the wall that connected you to a switchboard and a party line to a wireless device that uses satellite technology to connect you to the rest of the world. That's pretty dramatic. It didn't take very long, either, at just a little more than 100 years [source: Woodford].

ARPANET and the World Wide Web We have the U.S. military to thank for the Internet. During the 1960s, the Advanced Research Projects Agency (ARPA) began a project for the military designed to link up four important computers in case of a nuclear attack. To learn more about it, read How ARAPNET Works.

­Even though Alexander Graham Bell has been widely credited with inventing the telephone, an Italian immigrant named Antonio Meucci actually deserves that honor. Meucci filed an intention to patent the talking telegraph in 1849 but never proceeded with it, allowing Bell to file a patent for his version in 1876.

Today, cell phones are quickly replacing landline telephones. According to the Centers for Disease Control and Prevention (CDC) in a report covering the last half of 2007, nearly 16 percent of American homes used cell phones exclusively, and more than 13 percent of people received most of their calls via a cell phone even though they had a landline in their home [source: Blumberg]

Moving from advances in the way we use our phones to our passion for music, in the next section we'll explore recorded sound.

6: Recorded Sound

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Recorded sound has gone through some major changes since its inception.

Your MP3 player is a portable music machine that's small enough to fit in your pocket. It can store thousands of songs and play them back on command. You may define your mood by the music you listen to throughout the day and change your choices with a simple click.

Music clearly speaks to something deep in the human consciousness, and wherever we go, we take our music with us. Imagine a world in which there was no way to record sound. The only music would be live, created for the moment and then gone forever.
Although there were primitive attempts to reproduce sound as far back as 1500 B.C., it wasn't until the development of the phonograph in 1877 that we begin to see big developments in the science of recorded sound. The phonograph was the brainchild of Thomas Edison and used recording technology created by the French inventor, Leon Scott, a couple of decades earlier [source: Time Magazine].

Vinyl vs. Digital Sound Quality Those old vinyl records may have advantages over digital media. Where vinyl is an analog recording, closely copying the original sound wave, digital media takes a series of sound snapshots and puts them together. In the process, certain types of sound can be lost in the minute gaps between digital signals. If you think that drum solo is missing something when you listen to it in digital format, you're probably right.

­Edison's phonograph used a foil wrapped cylinder and stylus to record sound waves and play them back, something Scott's machine failed to do. Other inventors worked to improve his initial design, particularly the sound quality, including Alexander Graham Bell, who took out a patent on the phonograph in 1885 [source: Castleden].

Your MP3 player uses a hard disc and sophisticated compressed files to store music. MP3 recording software evaluates the sounds relative to the range of human hearing, the times a sound is repeated, and the overlapping sound pitch to compress files efficiently. Digital recordings use equally complex methods of recording sound using binary code. Whatever the method, if you're listening to recorded music, the process all started with a scratchy rendition of "Mary Had a Little Lamb" recited by Edison himself onto a piece of tin foil.

Want some pictures with your sound? Take a look at the next section where we'll discuss the next appliance you can't live without, TV.

7: Television

From the principle of photoconductivity and the phenomenon of visual persistence, the idea of television was born in the late 19th century. It took only 90 years to go from that modest beginning to the televised broadcast of the first moon walk in 1969.

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TVs just may be the most popular appliance in the world.

­Before television, people huddled around the radio to listen to news and entertainment programming. Before that, they relied on their newspapers and the entertainment value of their friends and neighbors. With the advent of the box with moving pictures and sound, the world was available at a flip of the dial. Although television didn't play a part in World War II, the end of the war brought an interesting and important development to television. The surrender of the Japanese in 1945 was broadcast over the fledgling television medium, bringing the drama and immediacy of current events to the minds and hearts of the public [source: Castleden] The NBC network, which began in 1939, started to grow, and television, an oddity that graced a few public bars and hotels, became a part of our collective consciousness.

There are more than 1.5 billion television sets in the world today, and that number is growing [source: Woodford]. New television technologies are vying with one another for supremacy, and the potential for the viewer to access and control the viewing experience is almost unlimited. Companion technologies, like the digital video recorder (DVR, TiVo), which allows viewers to schedule, automatically record and play back television programming, are gaining in popularity, and the future for the medium of television is bigger, brighter and sharper, and it couldn't be better.

Next, we'll see how America got cool and explore the next appliance we can't live without, the air conditioner.

8: Air Conditioning

Sunday Matinee The local movie theater used to be the best place to be on a hot day. Why? The air conditioning, of course. The local department store ran a close second. Retailers discovered soon after the introduction of air conditioning that a little cool air was very good for business.

­In the middle of a summer heat wave, it's great to have air conditioning. Before Willis Carrier invented his method of cooling indoor air, it was a challenge to stay comfortable in hot weather. A nice, cold drink was helpful, and some homes were designed to make the most of a light breeze, such as the traditional shotgun style homes. Even a nice, big tree for shade was great, but the promise of a temperature controlled home was still very appealing.

In 1902, Carrier's first air conditioner was built to cool a printing plant and remove some of the humidity created by the printing process. After taking out a patent for his design in 1906, Carrier started selling his air conditioning units for commercial applications. And in 1928, he released the Weathermaker, his first home air conditioner [source: Time].

Now that we've got our homes cool, let's get our food hot with the microwave.

9: The Microwave Oven

The First Microwave Ovens The first microwave ovens were very different from the countertop models we’re familiar with today. In 1947, the Raytheon Company’s first commercial units weighed a whopping 750 pounds (340.91 kg).

­With the introduction of the domestic microwave oven in 1967, the notion of meals in minutes became a reality [source: Idea Finder]. The average microwave can cook meat six times faster than a conventional oven [source: Woodford]. That means less time spent in the kitchen.

Microwaves were used in World War II for radar reconnaissance but weren't adapted for use in cooking until a happy accident occurred in the mid 1940s. Dr. Percy LeBaron Spencer, an employee of the Raytheon Company, accidentally melted a candy bar with radio waves. Microwave ovens use a magnetron tube that generates high-energy, short radio waves that agitate the water molecules in food, cooking it faster and more evenly. Taking advantage of this discovery, Raytheon's Amana division introduced the first commercial microwave in 1954 and followed up with a domestic model in 1967, the ®Radarange. It's estimated that 90 percent of American homes are now equipped with a microwave oven [source: USDA].

Next, we'll move on to one of the more recent inventions to permeate our lives: the computer.

10: The Computer

Although Charles Babbage is widely considered the inventor of the computer for the design of his mechanical "Analytical Engine" in 1840, like so many major technological developments, there actually are many people who contributed to the creation of the modern computer [source: Time].

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Although fairly new compared to some other appliances, the computer is incredibly popular -- at home and at work.

­The earliest computers without metal gears and switches were number crunchers performing mathematical calculations for the military. Used by the Navy in World War II, the MARK 1 computer was 55 feet (16.7 meters) long and 8 feet (2.4 meters) high [source: Behar] These early electronic computers used vacuum tube technology and were huge, hot and expensive to run.

Although the early years of electronic computing saw some miniaturization with the use of transistors and integrated circuits, it wasn't until the development of the microprocessor that the computer really became accessible to the public and captured the world's imagination. In 1977, the Apple II personal computer was introduced, followed by the IBM PC a few years later [source: Time]. These competitors brought computing to the masses. Refinements like the development of a graphical user interface (GUI) and a more intuitive operating system soon followed.

Within 30 short years, computers have revolutionized the way businesses work, people play and the world communicates. It's hard to envision a single aspect of human life that hasn't been impacted by the development of computer technology.