These are the most frequently used words in this book.
actions
another
between
button
call
car
case
change
come
computer
consider
constraints
control
design
designers
device
different
difficult
done
door
easy
errors
even
everyday
example
features
figure
first
function
get
go
good
hand
human
information
instruction
key
keyboard
know
knowledge
learn
left
lights
machine
mapping
may
memory
mental
model
move
must
natural
need
new
now
number
objects
often
operation
part
people
person
possible
power
problem
provide
put
required
result
right
seem
set
several
should
signal
simple
something
sound
still
structure
switch
system
take
task
telephone
things
thought
three
time
turn
two
use
used
user
visible
without
word
work
world
wrong