VOTERS across Scotland will soon go to the polls to have their say on who will run their local councils for the next five years.

But the single transferable vote (STV) system used for the local authority elections on May 5 differs significantly from the systems used to elect members of parliament.

When voting to send an MP to Westminster, each person gets one vote. When choosing MSPs in Holyrood, everyone gets two, one for the constituency and another for the regional list.

READ MORE: SNP criticised over 'incomprehensible' council election advice for voters

Under STV, voters don’t simply pick one person or party to vote for. Instead, they are asked to rank all of the candidates in order of preference.

People are free to rank as many or as few of the candidates as they choose, starting from writing a number 1 and working down.

Is it best to rank all of the candidates? Or only the ones you want to make it into council?

The short answer is: It’s best to rank everyone. STV allows voters to have an influence over the election success of every candidate that they put a number next to.

In the council elections, it is not only about getting more votes than your opponents. To win a seat, a candidate must reach a specific number of votes: a “quota”.

Once a candidate has reached that quota, their voters’ second preferences are then portioned out to the other hopefuls.

If no-one has reached the quota, then the candidate with the least first preferences gets eliminated, and their voters’ second preferences are portioned out.

By ranking everyone on the ballot, you can ensure that your vote gets transferred to a candidate you prefer, and avoid helping a party you do not like by removing your voice.

If you don’t rank everyone then your preferences stop mattering while others’ are still taken into account.

The National:

READ MORE: Pete Wishart: You really DO need to 'Vote Till You Boak' on May 5

As Pete Wishart (above), the SNP’s most senior MP, explained in The National: “If you only vote for your first preference then you remove yourself from the contests further down the line.

“You will have no say in whether a Tory gets in ahead of a less unpalatable independent, for example.”

Wishart’s advice seemed to contradict the official SNP line, which had been criticised for telling people only to vote for their party and not to rank any other candidates.

This advice to voters is in direct contradiction to that given by the Electoral Reform Society, which says it is a “myth that there is any advantage at all in not ranking a candidate in an STV election”.

The ERS says on its website: “If you see any encouragement to only vote for a certain party, or candidates with a particular viewpoint, that is equivalent to saying you should give up control of who else might get elected.”