A .zip file is compressed collection of files and folders. It's basically a convenient way to put a whole bunch of files and folders into a single file and then compress that file into a smaller size so it's easier to store and download.
If you do not already have a program installed on your computer for "unzipping" a .zip file, I recommend the following programs. (Don't worry, I have tested them and they do NOT contain spyware.)
.zip files often contain an internal folder structure, so when "unzipping" (uncompressing) a .zip file it is important to unzip it into a new, empty folder and to preserve the folder structure inside the .zip file.
Using your computer's File Explorer, create a new folder on your computer and then direct your unzipping program there, taking care to preserve the folder structure inside the .zip file. (Many unzipping programs have a checkbox to specify whether or not the program should preserve the folder structure or not. You must be sure that the program your using has this option set.)
After the .zip file is unzipped, you should verify that you've preserved
the folder structure by examining the folder where you unzipped the files
into. It should contain several other folders. For example, if you called
the folder you unzipped the program into "SnippetMaster",
then you should now see another folder called "includes" within
the "SnippetMaster" folder.
If you do not see any subfolders, please delete your "SnippetMaster" folder
and try again.