..but now I do!

We’ve all been given one at work as we’ve managed to go three years without mashing anyone one up and sending them home broken.

As I know nothing of these things, what should I do about Anti-Virus/Internet Security software? Is it needed? Always used it on my PC’s and Laptops ans never (touch wood) had a serious issue.

You don’t need antivirus, but don’t open odd-looking attachments on emails, as they could, possibly, enable your email account to be hacked.
As with any Mac, you are asked to give permission before opening/installing something that isn’t from the App Store or iTunes, if you don’t recognise it, don’t give permission, that’s what malware looks for.
Apps-wise, get WeatherProHD, MeteoEarth, Evernote, Dropbox, Flipboard, iBooks and Kindle, just for starters.
Then go and play… 😀