We've been discussing this in the Comms Room on Serverfault, and thought it might make a good question on SuperUser…especially if there's a clear answer. The hope is that it is a Good Subjective question.
Why do laptop screen sizes come in the fractional sizes they do instead of 11/12/13/14/15"? The most frequent I see advertised are 11.6", 12.5", 13.3", 14", 15.6". What's the reasoning behind it? keyboard size? ergonomics? resolution requirements? Most are LCD screens just like TV's, and yet TV's are advertised as whole numbers (19", 26", 46", etc.).
Looking at actual LxWxD dimensions on laptops doesn't really help since screen bezels vary in size.
example 11.6" laptop dimensions =
11.55" x 8.50" x 1.27" — this is due to a rather large bezel.
Whereas my x1 carbon touch, 14" diagonal screen but dimensions = WQHD Touch: 13.03" x 8.94" x 0.55" (Front)-0.79" (Rear) — again bezel…if it could be edge to edge that would be different, and "normal math" would insist the actual "monitor size" was about 15.5", which it is if you include the bezel.
Are there actual equations/ratios/mathematical factors in determining screen sizes on a laptop that make certain sizes more common than others? Note I stated screen size (like the common 11.6", 13.3", 15.6", etc.) and not actual dimensions of the monitor lid itself.
TO HELP CLARIFY THE QUESTION:
I'm asking why those particular fractional sizes are so common? Look at HP, Lenovo, and Dell. They all tend to go with those screen sizes. Is it because it is what the consumers are used to seeing/using? Is it dictated by resolution requirements that dictate the screen size (meaning 11.6" works out resolution wise, but 11.7" doesn't)? Or is it something else? If you want to hone in on one: Something somehow determined that 11.6" was a good common screen size…I'm curious what that was.