Preference votes refer to a type of voting system where voters are allowed to rank candidates in order of their preference. This means that instead of just casting one vote for their preferred candidate, they can also indicate their second and third choices as well. The idea behind this is to allow the will of the majority to be more accurately reflected by taking into account how people truly feel about each candidate rather than simply counting up the number of first-place votes.
In some countries like Australia, preference voting is used in elections for both houses of parliament and state legislatures. In these cases, candidates are grouped together on a single ballot paper according to their party affiliation or policy positions. Voters then have the option to either vote "1" above the line (which means they are essentially casting a group vote for that particular political party) or below the line (where they can number each box next to the candidate's name in order of preference).
Overall, preference votes provide an additional layer of complexity to the voting process but ultimately aim to produce more accurate and representative results.