Most of us know ZIP files. When a file with those three characters at the end appears on our computer file name (a.k.a. File Extension), we usually know that if we launch an application named WinZip, we’ll know soon enough what it contains.
A RAR file is essentially a condensed collection of files, it is another type of archiving program similar to WinZip. Sometimes, RAR files are referred to as a library, or a cabinet of files. These files use a compression technique to shrink and combine them into one handy file. They then can be sent through the Internet or e-mail in parts which can be re-assembled on the recipient’s computer.
WinRAR is the utility used to open RAR files.
Here’s a practical example. Your friend has a training video he wants to send you. You both have high-speed Internet, but don’t want to send it through the e-mail. What can you do?
The files in their native format are too big and difficult to organize. You would have a very hard time putting this all together again on your computer while maintaining the file and directory structure of the video.
With WinRAR, you collect the files and create a set of archives (also referred to as a spanned set of files) to be sent via e-mail, or to be put on a web site download link. You can also create archives on your computer to save disk space. Just about every file on your computer can be condensed by a certain amount. This depends on the type of file and the data. Movies and videos cannot be condensed as much as text files (as they are usually compressed already when they are transcoded, see Lab Rats TV Episode 40 – Codec 101 for additional information). The type of data contained in them makes all the difference.
Let’s suppose you need to send files as huge as 700 MB in total. You can use WinRAR to create a set of archive files (also referred to as a spanned set) that will create a sequential set of files for e-mailing. Typically, you can customize WinRAR to shrink the files according to speed, or level of compression. High compression means that your computer will work harder to decompress those files at the receiving end. Faster compression means that your computer will create the archives for a quicker decompression. You may also specify the size of the archive files to output.
For example, 700 MB would create about 70 files of 10MB each, with no compression. Once you have the files on your computer, locate the file with the RAR extension or the file with the lowest numbered extension (R01, R02 etc.) and open it to view the contents. Make sure you have all the RAR files in one folder (otherwise you can not reassemble the spanned set). WinRAR will sequentially number all the pieces, with RAR being the first of the set.
To unpack, simply drag the contents of the WinRAR window to your desired location. It will take some time, and you will see a progress bar. Also remember that you now have just used twice the disk space, as the extracted files are completely separate from the original RAR files you have received originally. And, by the way, there is also another program that can do similar things. It’s called IZArc.