Battery Chargers

To put it in simple terms, float charging is your basic trickle charge, going on all the time to keep the battery at its normal output voltage. It represents the current level needed from the charger to keep the bettery at nominal voltage level.

Equalizing charging is a short-term increase in the charge voltage, which translates to a higher charging current into the battery. This will "equalize" or balance the level of charge of the cells that make up the battery, to compensate for the fact that they are not all absolutely identical, and so they will charge and discharge to various levels. By equalizing, you are trying to get all the cells able to take their fair share of the load when operating. It tries to reverse some of the chemical effects that take place in the cells over their charge/discharge cycles.

Boost charging can be both another term for equalizing, or else a "fast charge" to try to bring up the charge level of the battery bank quickly, recognizing that this also puts more stress on the cells, causes more heating, etc.