Allegedly, on or about 28 May 2018, Angelo Moreschini sent:
I got the eclipse plugin "WB_v1.8.0_UpdateSite_for_Eclipse4.5.zip.md5" (plugin windowbuilder). The suffix md5 is for checking the integrity of the file...
But I cannot use this file (I cannot to install it on eclipse..) Nautilus doesn't unzip it, and also not the command ;ine tar -xzf.
If I rename the file (in .zip), nothing change.. and also I didn't find some program that can help me...
The file you're looking at with a .zip.md5 suffix, is not a ZIP file. It's a text file with a MD5 hash, or checksum, in it.
That's a descriptive text file *about* the other ZIP file. In this case a computation on the file, giving you a unique identifier that will only match the original file if it has not being tampered with.
e.g. example.zip (an archive) example.zip.md5 (a file about the archive)
The same kind of thing can be done with any kind of file, be that a binary ISO file, a directly executable file, etc. A separate checksum can be provided about that file, as a verification that the file is exactly the file it's supposed to be.
This does mean, however, that you need to get the checksum file from a source that you can trust.