Essentials are downloads that are the most needed in order to enjoy the Internet experience.
It is compressed so that it will take less time to download from the Internet. Zip filenames end in the extension .zip . If you download a file named something like filename.zip you will need Winzip to open the file and use it. ACDSee Friends who will email you pictures will send them in all sorts of formats. You need a program like ACDSee to look at them.