Compression lets you transfer files more quickly

November 14, 2010 at 12:00a.m.

As the name implies, anything that’s compressed is smaller than it was originally. In the kitchen, some of us still use compactors that compress our garbage so we can cram more of it into the same space. With computers, it’s our software that takes up space on our hard drives.

It used to be that our hard drives could only store a relatively small amount of software, so space was at a premium. Today’s terabyte hard drives have plenty of space on them and if we need more, buying a second one is very inexpensive.

Most of the compression we use on our personal computers basically deals with four categories. They are music, photographic, video and computer data. But technically it’s all digital data, the language of computers, which is all zeros and ones. And while we still use compression to save space, its main application is to save time. When exchanging files online, the smaller the file, the more quickly it gets transferred.

Along with e-mail, the sending and receiving of software online is one of the primary activities. Say you have a digital picture you took with your camera and you want to send it to someone. That picture may be megabytes in size. Even if you have high-speed Internet access, it will still take some time to send it to another location.

Photographs have an industry compression standard known as JPEG. Most photo-manipulative programs such as Photoshop will let you create a jpeg from your photographic image file. Since a jpeg file is typically many times smaller than the original image, you’ll be able to transfer that digital photograph a lot more quickly.

One of the most popular audio compressions is MPEG-3. Music files compressed using this standard contain the suffix dot mp3 (.mp3) after the filename. When it comes to audio, a CD can store around 13 songs. Using mp3 compression, a single CD can hold more than 100 tunes, and transferring them online can save you hours. But with any file you send or receive, be it a program, a word-processing document or any kind of data, compressing it down in size will expedite its transference.

To compress an application or data file, you have to decide what compression method you will be using.

On the Windows side, one of the more popular compression schemes is the Zip compression. Files that have been zipped usually end with a .zip suffix after the filename. On the Macintosh side, the most popular compression scheme is called Stuffit and uses .sit after the filename. To unzip or unstuff a file, you need to download one of the many free utilities to do so. Most of the popular compression schemes offer some sort of free decompression utility mainly because forcing someone to buy something before they can use your data is generally not a good idea.

If you plan to create compressed files, chances are you will have to buy a commercial or shareware program.

These compression utilities offer many extra features such as treating compressed files as though they were already decompressed. In many cases, you can actually view the contents of a compressed file without having to actually decompress it.

These programs also let you make self-expanding or self-extracting compressed files that expand automatically by double clicking them without the need for any decompression software. This method insures that whoever receives your compressed file will be able to immediately decompress it without the bother of having to locate a free decompression application.

Some companies and their compression products are PKWARE’s PKZip available at www.pkware.com and WinZip at www.winzip.com. For the Macintosh, Smith Micro (www.stuffit.com) publishes the Stuffit compression standard which is the one most widely used by the Macintosh platform. “Stuffit Deluxe” is available for both Macintosh AND Windows systems and the program works with all of the popular forms of compression including zip, sit, binhex and others. Check the websites of all these companies for different versions and pricing. Just a quick note, that while Windows and Mac OSX can natively do some levels of compression, these applications give you a lot more options.

So there you have it. Compression makes your files smaller so they take up less room on your hard drive or a CD, and it makes the sending and receiving of your files more efficient. These days, getting more done in less time is what compression is all about.

Craig Crossman is a national newspaper columnist writing about computers and technology. He also hosts the No. 1 daily national computer radio talk show, Computer America, heard on Business TalkRadio Monday through Friday, 10 p.m.-midnight ET. For more information, visit his website at www.computeramerica.com.

2010, McClatchy-Tribune Information Services