Digital Camera (Cheap ones)

[Dead Eye]

Ni-MH stands for Nickle-Metal Hydride which is basically the internals of the battery. Ni-Cad (Nickel-Cadium) are an alternative but are pretty crap from what I remember. Most batteries should be labelled, but for the most part just get a decent brand

The mAh is the mili-Amp hours. This is the number of hours the battery can continuously provide a current of 1 mili-Amp for before it is depleted. The larger the value, the more capacity the battery has and the longer it will last Good AA batteries are probably around 2,000-2,600 and this is again labelled on the actual battery

I THINK I got that all right, but I may be wrong in something. I'd look out for the mAh over anything else though, as this is what determines the capacity and therefore how long its going to last