Eric Ligman (Microsoft Director of Sales Excellence) does an annual giveaway of eBooks on many Microsoft products / services and products. Yes this is a shameless bit of promotion of Microsoft but the reality is that anyone in IT (or just the working world in general) will need to use Microsoft products so here is some free information about how they work and what they can be used for so you can look smarter than your colleagues.
Yes, this is designed to get you to buy more of their services.
Yes, the books are written as if Microsoft is the best thing since sliced bread (which is pretty damn awesome when you think about it).
Yes, Windows will crash from time to time and lose your work / scare your cat.
Yes, Linux / MacOS / open source projects can be better than Microsoft depending on the context and no I don't want to hear about your Arch system that you built from scratch that is SOO much better than anything else.
No, I don't work for Microsoft.
In case the 'Get Deal' link doesn't work the URL is https://blogs.msdn.microsoft.com/mssmallbiz/2017/07/11/largest-free-microsoft-ebook-giveaway-im-giving-away-millions-of-free-microsoft-ebooks-again-including-windows-10-office-365-office-2016-power-bi-azure-windows-8-1-office-2013-sharepo/