tkeepout in PCB design

Hi guys,

I am using the adafruit beaglebone cape for creating my own beaglebone cape. I observe that there are some red areas marked as tkeepout. Can we place components on that . Also what is the dotted line on the cape for?http://s22.postimg.org/5kn1un7dd/bone.png

“tkeepout”, is exactly what it sounds like. Keep Out. That means you can’t put anything there. This layer is usually designated for pads and heatsink pads.