The magazines are published in Portable Document Format (PDF)
the most popular format for publishing material on the internet.
Most computers will be able to open them.
If your computer says it can't open the file, then you probably need to install a program to read it.
These are free pieces of software, and you can get yours from
the inventors of PDF Adobe Acrobat Viewer (.pdf)
or from an independent firm such as Foxit Reader