Modified Sine Inverter
Modified sine wave inverters are a popular option with slightly compromised wave (some harmonics) at a lower cost. They approximates a true sine wave with low harmonics that do not cause problems with household equipment. Main disadvantage is peak voltage varies with battery voltage. Inexpensive electronic devices with no regulation of power supply may behave erratically when battery voltage fluctuates.
Not all modified sine wave inverters are created equal. A high quality modified sine wave inverter such as the Xantrex DR series will run 99% of loads without a problem.