There are many compression softwares available in market, the three prominent ones being WinZip, WinRAR and 7-zip. The new operating systems used these days are already equipped with couple of compression softwares. In case your PC doesn't have one, you could download it from internet. But simply having a software would not solve the issue - you need to know how to operate the same, if you really want to compress files and folders. Herein listed are a few easy methods that would help you compress bigger files into smaller ones.
Compressing A File
Using WinZip-Open the WinZip and click on 'New' icon. A window will open displaying the folders in your disk.
Scroll through the folders till you find a location to store your compressed data. WinZip will now create a file called archive. You can name the archive.
Click on 'Save' and you will return to the main window.
Now add the files you want to compress in the archive. You would have to click on the option 'Add'.
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Source: iloveindia .com

Using WinZip
Open the WinZip and click on New icon. A window will open displaying the folders in your disk.
Scroll through the folders till you find a location to store your compressed data. WinZip will now create a file called archive. You can name the archive.
Click on Save and you will return to the main window.
Now add the files you want to compress in the archive. You would have to click on the option Add.
In the compression menu, select the level of compression that you want. The option provided to you may range from Normal, None, Fast to Super Fast and Maximum.
If required, you can add a password.
Click on Add and you will return to the main WinZip window. Your compressed file is now added to the archive.