advice
advisory
alert
attention
background
beware
black
building
button
careful
caution
cloud
construction
danger
error
excitement
exclamation
fatal
gold
hazard
icon
industry
information
interface
internet
mark
message
point
precaution
pressure
reflector
risk
road
safety
secure
security
shadow
shiny
sign
signal
site
street
symbol
traffic
triangle
warn
web
yellow