A vote is measured by the amount of voting power it holds. The voting power for each voter is calculated using a strategy selected in the proposal. Depending on the Voting type, the voting power for each vote by voter can be distributed across multiple choices they may make. Let's look at each voting type.
Single choice voting
Each voter may select a single choice to give his total voting power to.
Each voter may select ("approve") any number of choices, each selected choice will receive equal voting power.
Each voter may spread voting power across any number of choices. The results are calculated quadratically.
Ranked choice voting (IRV)
Each voter may rank any number of choices. Votes are initially counted for each voter's top choice. If a candidate has more than half of the vote based on first-choices, that choice wins. If not, then the choice with the fewest votes is eliminated. The voters who selected the defeated choice as a first choice then have their votes added to the totals of their next choice. This process continues until a choice has more than half of the votes. When the field is reduced to two, it has become an "instant runoff" that allows a comparison of the top two choice head-to-head.
Each voter may spread voting power across any number of choices.