Z-Book vs 840 G - What's the difference/

[RangerZ]

I  manage a small fleet of 840 G1 and G2 laptops.  Looking at the service manaul it appears theZ-Book is "Family". 

I see that the Z-Books tend to have a second graphics adapter (as did some of the 840's, but it's different).  I also see some differences in the cover and keyboard bezel color(grey vs silver).

Are there any other differences like a sturdier case?

I am not keen on the basic Intel adapter quality on 4K.  Are the adapters in these any better?

[soccer_dan]

EliteBook is the top-end business notbook family that includes security technology like HP Sure Start, BIOS self-healing. The Elitebook line has 2 families, the 800 series and the 1000 series (with the thinnest, newest technologies and materials, and which are mostly x360 hybrid designs). The Zbook  family is the performance series with additional graphics and capacities, and provide ISV (software) certifications for industry-wide design and engineering applications, like AutoCad, Adobe Creative Suite, and many, many others

Hope this helps

[RangerZ]

Thanks you, but a bit more high level than I was hoping for.  Can you dial this back specificaly to the 840 G1 and G2 and thier Z-Book bretheran?

What is "x360 hybrid designs" and is it relevant to the older G1 and G2?