Zip, unzip it! – How to compress files
There
 are two possibilities to compress files on windows. You could use a 
third party program or the already implemented compression tool of 
Windows. Since Windows XP it is possible to create compressed zip-files.
Compressing
 files has many advantages. First of all it could safe your space and 
time e.g. when you transfer couple of files over the internet or to your
 USB flash drive. You could also split large files into small pieces or 
protect them with a password. Downloadable programs are sometimes 
offered as compressed files to have safe traffic over the internet. The most 
common ending for a compressed file is “.zip” due to the fact, that 
Windows is using this format to compress files, so when you use a 
different compression tool you should always take care about the recipient of
 the compressed file, because not every person has installed a third 
party program which supports multiple formats such as “.rar” or “.7z” 
formats. 
So, but how do we compress files with Windows 7? It’s pretty 
easy:
1.       right click on the file
2.       go to the option “send to” and 
3.       select “Compressed (zipped) folder”, 
That’s
 it! You now have a new file which can be renamed. Double-click 
on that file which will open the explorer and show your compressed file. If 
you would like to compress a couple of files you can select them all 
and then repeat the tutorial or put them together into a folder and 
compress the folder.
Extracting a compressed Zip-file can be also done in four steps
1.       right click on the file
2.       go to the option “extract all” – a new window opens
3.       select the destination where to extract you files and 
4.       then click “Extract”
By default the destination of your extracted files is the same place where your compressed file is located.
Here are two additional video tutorials which show how to zip or unzip with Windows 7 in less than a minute.
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