Well, now that you mention it, the main difference is - - - price.
Seriously, if your objective is to provide physical protection for the front element of your lens, then any of these will serve. The differences in price represents how well they function optically (ie, which introduce less distortion) and how well they function as UV filters (which means how well they address light balancing in situations where there is an abnormal amount of UV present, for example, in the mountains on a very clear day). And of course there is the matter of price - some filter manufacturers choose to market themselves at the 'premium' brand and charge a higher price just for that.
You characterize yourself as 'a complete novice'. On that basis, I would venture to guess that you won't notice the optical effects of a UV filter. And you very well might not be able to see whatever distortion that a filter introduces.
There is a long tradition in 35mm photography for manufacturers and retailers (especially retailers following the "sell that sucker something else" approach to marketing) to recommend either a UV or a 1A (or skylight) filter to 'protect the lens'. In theory, the presence of any filter degrades the image to some degree, and purists would argue that the only time you should use a filter is when you need filtration. And it is true that having a filter on a lens will protect the front element of the lens from fingerprints, grit, scratches, etc, and replacing that filter is less expensive than replacing the lens.
I have a 1A filter on each of my 35mm lenses. Yeah, I know it's probably unnecessary, but I followed 'conventional wisdom'.