Thank you for your input Wallaby Dan, but is this anything an almost 80 year old non-computer-whizz should be concerned about and if it is, what can I do about it?
I meant to mention in my original post that I have also had messages appear in the bottom right hand corner of my monitor. This message says that Windows defender has recognised virus threats and I need to take action. I've only remembered this because one just appeared after I logged-on just now. When i looked yesterday there were a number that were labelled as 'severe' and some as 'medium'. I seem to recall that I had the option to 'ignore' 'quarantine' or 'remove' them.
I didn't know what I was doing so I simply removed them. I recall that the word 'trojan' was mentioned at some point.
Is all of this any cause for concern and is action needed outside of me just 'removing' them?