Whats the difference between a gas oven and a electric oven?

Besides the obvious difference of energy source, gas and elecric ovens have some other important differences. 

All contemporary ovens come equiped with some kind of temperature regulating device, or thermostat.  When the user sets the temperature on the front of the oven, the thermostat works to regulate the set temperature inside the oven.  On a gas oven, the thermostat closes the valve that supplies gas to the burner inside the oven when the set temperature is reached.  When the temperature drops below the set temperature, the thermostat turns the valve back on and relights the burner.  On an electric oven the thermostat works in basically the same way.  Electric current is supplied to the heating element when the temperature in the oven is below the temperature set by the user.  When the oven temperature reaches the set temperature, the thermostat interrupts the current going to the heating element. 

Thermostats are not completely accurate, and thermostats on electric ovens are typically more sensitive than those on gas ovens.  On gas ovens, the temperature in the oven may vary by as much as 25º F.  This means that if the oven is set at 350º F, the temperature may vary inside the oven from 325-375º F.  The thermostats on electric ovens typically keep the oven temperature to within 5-10º F of the temperature set on the front of the oven.  

Consumers looking for a new oven may also be interested in other considerations.  Fuel cost is not usually a consideration since ovens use relatively little energy compared to other household equipment.  But gas appliances are generally more efficient than their electric counterparts.  However, if there is no pre-existing gas piping in the house installation could get quite expensive.  Also, gas ovens need to be set up for either natural gas or LP (propane) gas depending on the consumer's gas supply.  Furthermore, some consumers may prefer old-style gas ovens with a pilot light in the oven because they do not require electricity to operate. 

In conclusion, electric ovens have better temperature accuracy than gas ovens.  But some consumers may prefer gas ovens due to energy efficiency or other considerations.