Networking for Dummies is the best-selling beginner's guide to computer networking: set up and maintain a network, ensuring best practices and much more. You can get the ebook free of charge with your email address or by connecting via LinkedIn. The offer is only good until July 26.

Amazon's Deal of the Day is a certified refurbished Samsung U28E590D 28" 4K monitor. We picked this monitor as a great buy back in 2015 as an affordable 4K option, but $270 is ridiculously low even for a refurbished unit. Of course, you're not getting state-of-the-art specs, but user reviews back it as a solid 4K offering for desktop work (not so much for gaming, in spite of FreeSync support). If you're coming from an old monitor, this will do great as a cheap upgrade, however note this is an affordable model with no height or swivel adjustments.

Secure your Linux machines and keep them secured with over 50 hands-on recipes to create and administer a secure Linux system locally as well as on a network. You can get the ebook free of charge (a $25 value) with your email address or by connecting via LinkedIn. The offer is good only for a limited time.