I was downloading a zip file on IE. Because the net was slow, the download completed incompletely. Why?

I was downloading a zip file on IE. Because the net was slow, the download completed incompletely. I downloaded other files some videos and they completed "complete downloads" even when the net was slow. Now i am using a download manager and the problem is gone.Can anyone tell the reason as to why this is happening?

I was downloading a zip file on IE. Because the net was slow, the download completed incompletely. Why?
The Server you were downloading from could of "Timed Out" this would drop the download, and the Download Managers, use a technique where they ping several different download sites, and download parts of the file from the different download sites, and when finished, it put's them together to make the file... Good Luck

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