Improve documentation

doc/hardware.txt

@@ -0,0 +1,30 @@
+# Running Collapse OS on real hardware
+
+Collapse OS is designed to run on ad-hoc post-collapse hardware
+build from scavenged parts. These machines don't exist yet.
+
+To make Collapse OS as likely as possible to be useful in a
+post-collapse world, we try to give as many examples as possible
+of deployment on hacked-up hardware.
+
+For example, we include a recipe for running a Sega Master
+System with a PS/2 keyboard plugged to a hacked up controller
+cord with an AVR MCU interfacing between the PS/2 connector and
+the controller port.
+
+This setup, for which drivers are included in Collapse OS, exist
+in only one copy, the copy the author of the recipe made.
+
+However, the idea is that this recipe, which contains schematics
+and precise instructions, could help a post-collapse engineer
+to hack her way around and achieve something similar. She would
+then have a good example of schematics and drivers that are
+known to work.
+
+If you want to run Collape OS on real hardware, take a look at
+arch-specific documentation in /recipes and see if some of the
+supported hardware is close to something you have.
+
+Easy pickings are PC/AT (which run on modern PCs supporting
+legacy BIOS), Sega Genesis w/ Everdrive and TI-84+. Those
+options don't require any soldering.

doc/intro.txt

@@ -13,7 +13,7 @@ improved in a world without modern computers.
 # Forth
 
 This OS is a Forth. It doesn't adhere to any pre-collapse stand-
-ard, but is pretty close to the Forth described by Starting
+ard, but is pretty close to the Forth described in Starting
 Forth by Leo Brodie. It is therefore the recommended introduct-
 ory material to learn Forth in the context of Collapse OS.
 
@@ -31,3 +31,23 @@ it should.
 
 This documentation is expected to be printed before the last
 modern computer of your community dies.
+
+# Where to begin?
+
+If you're reading this and don't know where to begin, you're 
+likely to have access to a modern computer. The best place to
+begin is to build the C VM of Collapse OS in /cvm. You can then
+begin playing with it with the help of usage.txt and impl.txt.
+
+When you're ready to move to real hardware, read hardware.txt.
+
+# Other topics in this documentation
+
+* Dictionary of core Forth words (dict.txt)
+* Editing text (ed.txt)
+* Assembling binaries (asm.txt)
+* Programming AVR chips (avr.txt)
+* Bootstrap Collapse OS to a new system (bootstrap.txt)
+* Cross-compilation mechanisms (cross.txt)
+* Protocols (protocol.txt)
+