I've reviewed Webster & American Heritage & think I've got a good grip on the definitions of "electric" and of "electronic", but am not clear on when it is appropriate to use one or the other.
Is my computer electric, electronic or both? What about a light bulb, a flashlight, my digital watch or my brain?
Is my computer electric, electronic or both? What about a light bulb, a flashlight, my digital watch or my brain?
Your computer works with electricity, but formally speaking it's an electronic apparatus. A digital watch is also electronic although it works with electricity supplied from a small battery. A light bulb and a flashlight, which is pretty much the same thing, are electric appliances. Believe or not, your brain is electric. 
Electronic is used to refer to equipment, such as television sets, computers, etc., in which the current is controlled by transistors, valves, and similar components and also to the components themselves. Electrical is used in a more general sense, often to refer to the use of electricity as a whole as opposed to other forms of energy: electrical engineering; an electrical appliance. Electric, in many cases used interchangeably with electrical, is often restricted to the description of particular devices or to concepts relating to the flow of current: electric fire; electric charge.
Hope this helps!
...and Happy New Year!

Electronic is used to refer to equipment, such as television sets, computers, etc., in which the current is controlled by transistors, valves, and similar components and also to the components themselves. Electrical is used in a more general sense, often to refer to the use of electricity as a whole as opposed to other forms of energy: electrical engineering; an electrical appliance. Electric, in many cases used interchangeably with electrical, is often restricted to the description of particular devices or to concepts relating to the flow of current: electric fire; electric charge.
Hope this helps!

...and Happy New Year!
Comments
your computer, radio, TV, etc are electronic devices. Those electronic devices need to use electric current.
I am from Bangladesh.
thanks
Khorshed
Per answers.com, Electronic means:
The use of electricity in intelligence-bearing devices, such as radios, TVs, instruments, computers and telecommunications. Electricity used as raw power for heat, light and motors is considered electrical, not electronic.
Although coined earlier, "Electronics" magazine (1930) popularized the term. The magazine subheading read "Electron Tubes - Their Radio, Audio, Visio and Industrial Applications." The term was derived from the electron (vacuum) tube."
Edited to fix formatting.
We're always happy to welcome new people, but finding a more recent post, in which the person is likely to still be around to benefit from your response, is probably a better use of your talents.
DC level voltages ranging from 24 volts to 5 volts at the DC power supply. For example, the modular power converter for your cell phone is called a power supply which convert the 120 v- ac to around 5 v -DC. AC -alternating current cycles between positive 60 v-ac to negative 60 v- ac at the rate of 60 cycles per second. The +60 and the -60 vac is called the peak to peak sine wave voltage. If you would look at any electronic product lable in the US, it will say " 120 v-ac 60 herzt". That's the electrical requirement for the US. In Europe, it's 220/ 240 v-ac. Electronic products must have the AC power as input source which is reticfied through a bridge reticfier before the AC is converted to some level of DC (direct current). All the rechargeable batteries are devices that store the converted AC to CD power so that portables like laptop and palm pilot can operate on the go. That's basically the nutshell about electric and electronic.
there's no "standard" definition of the difference between electric and electronic circuits or devices. I can only tell you the most popular one, the one you'll find in most books about electronics. In brief:
- An electric circuit does not contain active components. Electronic circuits contain active components. Active components are the ones that appear to generate power. The most common active components are transistors.
According to that definition, your PC has transistors and is an electronic device, a light bulb does not have any transistors and is an electric device.
You have to remember that that definition is NOT accepted by everyone, but it's the most common. As I said, there is no official distinction, and there is no need to find one either. I, for example, don't usually distinguish between electric and electronic according to the above definition. I have a personal one