I thought we were pretty much past corrupted downloads at this point in the century, but apparently not.
I’ve been doing some software work recently, and I needed to download a demo compiler. The download completed, and I started the install, but it never finished. It turns out that the install crashed because it had managed to fill up the 20GB of free space in my Windows virtual machine. And that happened because the installer file was incomplete and it went off into the weeds.
Three download attempts and two hours later using a total of two OSs and three different browsers, I finally got the complete file. (Especially disappointing given that the full version of this compiler is rather expensive.)
So Pro Tip: always at least check file sizes. Also on OSX you can calculate the MD5 checksum of a file from the terminal using:
$ md5 myfile
On Windows, there are several free utilities a Google search away.