Getting CPU temp from the command line

What is the best way to get the CPU temperature on Linux from the command line? On one small portable system, I was able to get the CPU temperature from here:

/sys/class/thermal/thermal_zone0/temp

or here:

/sys/class/thermal/thermal_zone1/temp

However some people say to look for the "coretemp" value, which doesn't seem to exist on my system. Is there an official best practice for getting CPU temperature?