The change is excellent, James - makes the visibility / readability much better.
Chris, Verdana and Arial are MS fonts that come with MS products (such as MSIE, etc.)
If no MS products have been on a machine (yes, there ARE people who don't use Windows) there is a chance that those fonts won't be available. 4 of my machines do not have them.
Usually they are paired with Helvetica, since that is the closest general system match to the specific MS supplied fonts.
James, one must be cautious using fonts on-line since if you don't include a similar font from each major OS, the text will display as the default the user has chosen, and sometimes that's not pretty ...
There are three main sets of fonts that can be used and those are the serif (times roman, etc.) sans-serif (helvetica, arial), and generally a monospaced typeface like courier / new courier.
Using others makes the chance of the end user not having it much higher, and then dropping to the default ...
Take care,
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