You've seen them everywhere, with their earphones connected to college students, gym-goers and people traveling by public transportation. They are used for listening to your favorite music tracks and for drowning out surrounding noises. They are the ever popular, portable MP3 players.

MP3 is an audio file format that compresses music files. The compressed audio files can be stored on your computer and transferred to a portable MP3 player for listening to on the go. MP3 players have come a long way since first being introduced. When they were first launched they could barely hold 20 to 30 songs. Today some MP3 players can hold up to 40,000 songs--that's over 1,000 hours of continuous music!

The Giant That Is iPod
The MP3 player that is most dominant is the Apple iPod. Released to the public on October 23, 2001, it has gone through fifteen alterations ranging from different sizes, colors and memory capacities. It quickly became the most popular portable MP3 player, and Apple has sold more than 140 million of the various versions of iPods, including current models like the Shuffle, the Nano, the Classic, and the Touch.

The iPod distinguishes itself from other MP3 players on several levels. While still an MP3 player at heart, the iPod supports several audio file formats. Like other MP3 players, iPods support MP3, WAV, and AAC/M4A. What sets iPods apart from the rest is that they also support the protected file format ACC, which can only be purchased through iPod's digital media program iTunes.

iTunes is a free software that can be downloaded to your computer for use with your iPod. It allows consumers to store, organize and purchase music through the internet and have it all sent, by USB connection, to your iPod.

iTunes is not the only music provider online. Companies like amazon.com, Rhapsody Music, and eMusic allow customers to set up accounts and purchase music. While not offering a selection as large as iTunes, they do provide special deals and competitive pricing that may convince the consumer to sign up with them in addition to iTunes.

Breaking the iPod Barrier
The iPod is the best selling MP3 player on the market; however it is not the only available model. Sony and Samsung provide consumers with several different kinds of models that have functions that cannot be found on any iPod.

All Sony MP3 players allow for easy uploading of music and files, to and from your player to your computer. Simply plug it into the USB outlet, on your laptop or desktop, and you can click, drag or delete files at your leisure. No need to install iTunes or any other file reading program. Some Sony MP3 players allow you to receive AM or FM broadcasts with a small, built-in antenna that can receive a signal just as any modern radio can.

The Samsung models, while not able to receive broadcast signals, provide the consumer with ease of use just like the Sony. Samsung also provides one of the smallest MP3 players. Designed to look just like a "pebble," it is small, round and fits conveniently in almost any pocket.

Thanks For The Memory
How do all these songs fit in such a small device? MP3 players and iPods have varying memory capacities.

Much like an actual computer, the iPod is the only brand of MP3 player that supports an internal hard drive memory that can be used to store music, photos and files directly onto the unit. Storage capacity can range from 1GB to 160GB. Outside the iPods, MP3 players support the various memory sizes in the form of a compact flash drive (the 1GB and 2GB iPod Shuffles also employ flash drives).

So what's the difference between the two? There are pros and cons for both. The flash drives allow for fewer moving parts. The songs are read off of a microchip, eliminating skipping that may occur on a hard drive. The downside is the decreased amount of storage compared to a hard drive.

Podcasts
MP3 files are not only limited to music. With the development of portable MP3 players came the development of podcats. A podcast is an MP3 file that is much like an actual radio broadcast. The length of the broadcast can range anywhere from 30 minutes to two hours, presenting conversational radio-style shows. Genres include sports, entertainment, music, video games, talk radio and even consumer at-home independent productions. These can be downloaded off of websites or iTunes. They are always free and always entertaining.

Video Too!
As with all technology, MP3 players have evolved, and newer models now support the video format MPEG4 that lets you watch your favorite TV shows and movies right on their screens.

The newest version of the iPod, the iPod Touch, provides consumers with the largest viewing screen available on the market. Boasting a large, 3.5-inch touch screen, the Touch allows consumers to download shows and movies directly off iTunes. TV shows can be purchased for $1.99 an episode and movies can be rented at $2.99 or $3.99 for new releases. Don't feel like turning on your computer and hassling with wires for connectivity? No problem! The Touch supports Wi-Fi internet access and consumers can download music, movies and shows off of iTunes without the need for wired connections.

Newer DVD and Blu-ray movies that can be purchased at your local store have the ability to "digital-transfer" video to your computer. This means that your favorite new release can be uploaded to your computer, converted to MPEG4 format and downloaded directly to your MP3 player. Never be without your favorite flicks!

Fancy Phones
The development of newer phones and the increased access to various forms of media have allowed cellular phones to also slowly become portable media giants. Ahead of the pack is the Apple iPhone. Similar in size and capacity to the Touch, the iPhone has all the features of a Touch, including music, videos,GPS and Wi-Fi, but adds the ability to make and receive phone calls.

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