If you want to see an example of democracy in action, look no further than those members of the public heading down to their local school, church, or leisure centre to cast a vote on election day.
Yet, there has been a rise in popularity over the years for voting in elections (and referendums) by post.
Backers of the system say it improves turnout - but critics argue it's wide open to fraud.
As people taking part in the Scottish independence referendum receive their postal votes, here's a look at the history of the service.
Born from conflict
It may seem hard to believe that voting in elections was once done with a show of hands, until 1872 when private polling stations were brought in.
The next logical step was not having to turn up at all, and so the "absent vote", allowing people to have their say by post - or naming someone to do so on their behalf - has been around since 1918.
At first, it was only allowed for members of the armed forces still serving overseas at the end of the First World War (with a similar arrangement made for WWII.)
Civilians weren't allowed a postal vote until 1948 - and even then had to give a good reason why they couldn't make it to a polling station on the day, for example being physically incapacitated, or for work reasons.
Vote from the beach
It seemed postal voting was here to stay, yet in the early 80s, there remained significant concern - voiced at the time by Westminster's Home Affairs committee - about extending the service to anyone who wanted it.
The main worry was that people casting votes outside the security of a polling station could fall victim to coercion or bribery, while there was also scope for individuals to vote multiple times by using other people's identities.
The government of the day agreed, saying postal votes should continue to be confined to those unable to vote in person on polling day.
However, this position also meant people away on holiday during election time were added to the eligibility list.
The new arrangements became law in 1985, with the exception of Northern Ireland, where there was widespread concern about electoral abuse.
Thinking outside the (post) box
By the dawn of the noughties, there were concerns the absent voting system had become too unwieldy, and was crying out for reform.
Eventually, a review in 1999 chaired by Home Office minister George Howarth said anyone in England, Wales and Scotland who wanted a postal vote should get one.
In the following year's council elections, several English local authorities dispensed with polling booths altogether in some wards, in favour of postal voting.
Turnout in some areas increased by as much as half, while there were no reports of major administrative problems.
Postal voting went on to get its biggest show yet in the 2001 UK election, where it was made available "on demand" - an offer taken up by almost 4% of the electorate.
Following that, the 2004 European Election saw the use of all-postal voting areas in the North East, East Midlands, North West and Yorkshire and Humber.
The Electoral Commission watchdog noted an increased uptake. - but concerns remained.
'Open to fiddles'
Back in 2004, the elections watchdog said there was no evidence of widespread abuse of the system, but some politicians were extremely sceptical.
Conservative MP Alan Duncan told parliament that all-postal voting left "massive scope for fraud and undue influence", adding: "It is, at every turn, open to fiddles".
Christopher Leslie, Labour's constitution minister at the time, said despite the issue having "excited the opposition and garnered many column inches in the press", the allegations had not been fully scrutinised.
There's never been any real evidence of systemic abuse of the absent voting system in the UK - although there have been a few notable cases.
In 2005, judge Richard Mawrey QC delivered a scathing assessment of the system, after ruling there had been "widespread fraud" in six Birmingham council seats won by Labour the previous year.
He said the case reached levels, "that would disgrace a banana republic".
That same week, former Labour councillor Muhammed Hussain from Blackburn, Lancashire, was jailed for three-and-a-half years for rigging postal votes, after he arranged for campaigners to ask people to hand over blank voting papers, telling them: "Don't worry, we'll take care of them."
And in 2006, two Liberal Democrat councillors, also from Lancashire, were jailed after collecting signed proxy vote forms door-to-door during the 2004 council elections, which they filled in themselves.
To this day, Mr Mawrey maintains postal voting is open to fraud on an "industrial scale", but the Electoral Commission says it would not be proportionate to end postal voting altogether.
Referendum by post
Just like in elections, many people in Scotland have registered to vote in the independence referendum by post.
More than four million people get to vote on 18 September, and the number of people with a postal vote went up from 570,587 in March to 680,235, as of 15 August - an increase of about 20%.
You can apply for a postal vote through the Electoral Commission - and remember, you must be registered to vote by midnight on 2 September.
The application deadline for a postal or proxy vote is 17:00 the next day.