There are basically 2 types of inverter: cheap ones and expensive ones. :D
Both types take a 12v DC supply and convert it to a 240v (ish) AC supply, so you can plug in a 3-pin plug and run normal domestic type appliances.
The cheaper ones do this by turning the DC into a stepped AC waveform. This is fine for most purposes, but I've found with some power supplies (I suspect it's mainly switched mode ones), such as for laptops & cameras, these inverters don't supply a clean enough waveform for the power supply to work properly.
So then you get yer pure sine wave inverters, which use more costly and bulky electronics to give a nice clean sine wave, instead of a clunky square wave.
Stu, your inverter will almost certainly be fine for most things, providing they're not rated over 120W. So don't plug the angle grinder in! If you have any problems running things such as laptops off it, you might want to consider a pure sine wave inverter, but they're a lot more costly.
