How to zip a file or folder
Why are there so many different zip programs?
You've got me. I think the first one I remember using was WinZip. They had an evaluation version that you could use indefinitely, but every time you used the program you'd get a start-up screen that gave you the option to buy the full software. I'm still not sure what benefits there were to buying the program other than getting rid of the start-up screen.
There are now many different programs out there for zipping and unzipping files and folders. My current favorite is 7-zip. It's free software and there's an entire online community of support. You can find the program at 7-zip.org.
What else can 7-Zip open?
7-Zip can handle of bunch of different files, including .zip, .rar (very popular), .jar, .iso, and .chm.
Opening a zip file
As long as you have an operating system made since Windows Millennium Edition (the god-awful ME came out in 2000, chances are your computer is newer than that), you should be able to unzip a file without any third party software. Right click the zip file you want to open and select open or explore. Cut the files that you want and paste them into the folder where you want to put them. It really is that simple.
Zipping a file or folder with 7-Zip
7-Zip is great because it's cross-platform, which means the file you create after zipping a file or folder can be unzipped with a variety of operating systems. The standard file extension for a 7-zip file is .7z, but it can also create files of other formats.
After downloading and installing 7-Zip, just right click on a folder you want to archive and then click on 7-zip from your list of options. From there you'll be able to select things like the file extension you want your archived file to have.
What's the point of archiving programs?
There are several benefits to creating an archive file instead of just having a folder filled with a bunch of files. For one, it takes that folder with files and turns it into one file. That makes it easier to send it as an email attachment.
The other reason to archive a folder is to compress the file size. Programs like 7-Zip will create an archive file that is actually smaller than the sum of its parts. Don't ask me how they do it, but by compressing the files they also make it easier and quicker to send the files around the internet. This is why so many bittorrent files are packed as archives.