"What Are zip/rar/7z Files?"

Think of the way a folder works in Windows. You drop contents into a folder to organize your files, and then you can transport that folder to any location on your computer, and the files inside of it go with it.  Zip files work in a similar way, except the contents inside the “folder” (zip file) are compressed to reduce storage use.

What if you have a folder that contains 20 files, and need to email it to someone?  Well, you can’t email a folder to someone, so you’d have to email the 20 individual files.  That’s where zip files become really useful, because you can “zip up” those 20 files into a single zip archive, and then email it.  Along with the convenience of having all those files in a single zip archive, they’ll also be compressed to reduce storage and make transmitting them across the internet that much easier.

"Okay, but how does it matter to me who just wants to play Dray's hacks?"

What you just downloaded in the previous step was a zipped file, either in .zip or .rar format. You don't want the zip file itself, what you actually want is the files inside it (which include the hack patches, patching instructions and documentation detailing the changes). Therefore, to actually get those files out of the zipped file, you need to unzip it.

To do this on Windows, you'll need 7-zip (https://www.7-zip.org/) or WinRAR (https://www.rarlab.com/download.htm). Create a new folder for your downloaded hack. Open the zip with either program and extract all the folders and files inside it to your new folder by simply dragging and dropping.

Mac has a built-in utility for the purpose - https://www.lifewire.com/how-to-zip-and-unzip-files-and-folders-on-a-mac-2260188

If you're on Linux, you're technical enough to know all this stuff already. What are you even doing reading this? But psst, don't tell anyone, you're my favourite ;)

Once you're done with unzipping, continue with the rest of the steps in the post!

Credits to How-To-Geek for the simple explanation: https://www.howtogeek.com/178146/htg-explains-everything-you-need-to-know-about-zipped-files/