The files are not damaged or changed, just stored in a different way. A good analogy is to think of it like taking a large letter, folding it up and putting it inside a small envelope. You send the envelope which now takes up less space, but at the other end the envelope can be opened and the large letter folded out again.
This is the advantage of using compressed files. You take a large file or group of files, compress and place in one small compressed file, then send. At the other end the contents can be "extracted" back to their original size and used as normal.
WinZip is the most well-known of many programs able to compress files, in this case to what are known as Zip files with the filename extension .zip
Installing WinZipYou can download a trial version of WinZip from www.winzip.com
After the trial period is over you will be reminded to purchase a License to continue using the program.
Choose a site to download from and click Download Now. Choose to Save To Disk and choose a location on your computer to save to.
Double-click the winzip file you have downloaded to begin installation. Click Setup then OK to install to your Program Files folder. As you proceed through the setup options you will need to click Next to move on to the next screen.
Click Yes to agree to the License Agreement. You can now view or print a Quick Start guide if you wish to. Choose Start with the WinZip Wizard.
Choose Quick Search and after a few seconds WinZip will finish making a list of your folders. The setup will also need to associate WinZip with various filetypes. When WinZip Setup has finished, click Close.
Using WinZipTo start the program, double-click the WinZip shortcut on your desktop, or alternatively click on the Start menu then All Programs > WinZip > WinZip.
Click on Use Evaluation Version. You should now see the WinZip Wizard, which helps you perform the most common tasks associated with WinZip. Click Next and for this example, Create A New Zip File.
Choose a filename such as "ZipTest" which will be saved to the default folder, or use Browse to choose a different folder, enter the filename and click OK.
Click Next. Use the Add Files button to add the files you want to compress, or you can click and drag them into the empty box. When you have added the file or files you want to compress into this Zip file, click ZipNow then Finish.
WinZip will close and if you now look in My Documents or whichever folder you specified earlier, you should see a .zip file called "ZipTest". To open this or any other Zip file, in Windows XP you can double-click it as if it were a normal folder. From here you can drag the files out, which will extract them so they can be used as normal.
Alternatively, right-click the file and choose Open With WinZip. Click Evaluation Version and you should see the Wizard again.
Click Next then UnZip or Install from "ZipTest.zip". Click Next and choose a folder to extract the contents of the Zip file to (the default location is a folder called Unzipped in My Documents).
Click Unzip Now. In the folder you specified you should now be able to see the files you originally compressed in the Zip file, extracted and ready to use again. Click Finish in WinZip to close the program.