The Old Firm derby pits Glasgow giants Celtic and Rangers together in what remains one of Europe's biggest and fiercest local rivalries.
The Scottish giants have dominated as the top two in the country for decades and when they meet at either Celtic Park or Ibrox it's always a huge occasion.
The bitter rivals are without question the two biggest, most successful and best-supported clubs in Scotland and they have played out many a memorable Old Firm derby match down the years.
It's unclear where the term 'Old Firm' to describe the Glasgow derby derives from, but it could be from the two clubs' initial match in which the commentators reportedly described the teams as "like two old, firm friends".
Another suggestion is that it was taken from a satirical cartoon published in 'The Scottish Referee' sports newspaper before the 1904 Scottish Cup Final between the sides, when an elderly man with a sandwich board was depicted with a caption alongside that read: "Patronise The Old Firm: Rangers, Celtic Ltd".
Celtic currently have the bragging rights after winning the first Old Firm derby of the season on 3rd September at Ibrox 1-0, thanks to Kyogo Furuhashi's goal.
The two rivals are next scheduled to meet in the traditional Christmas/New Year showdown, which this time takes place on 30th December at Celtic Park, kicking off at 12:30.
With Celtic currently eight points clear of their local rivals at the top of the Scottish Premiership, it's no surprise to see them available at 1/5 to go on and win the title this season, while the second-placed Gers, who do have a game in hand, are 7/2.
Both Celtic's famous Celtic Park stadium, which is also known as Parkhead, and Rangers' iconic Ibrox home host Old Firm derbies.
However, the two sides have also often meet in cup competitions at neutral venues, most frequently at Glasgow's other famous stadium and the historical home of Scottish football - Hampden Park.
The first Old Derby derby of the 2023/24 season was shown on Sky Sports and the same broadcaster will show the 30th December meeting with the game live on Sky Sports Football and Main Event.
There have been 437 Old Firm derbies in all competitions to date. The game is one of the longest-running derbies in world football.
Rangers just have the edge, winning 169 derbies, whilst Celtic have won 166 and the pair have drawn 102 times.
Including several youngsters who had spells at either Rangers or Celtic's academy before going on to play for the other side, records show there have been 33 players who have played for both Old Firm clubs.
Some of the most famous names to pull on the Light Blue jersey of Rangers and also wear the Hoops of Celtic in recent times include Mo Johnston, Kenny Miller and Steven Pressley.
Centre-forward Johnston was a controversial signing for Rangers in 1989 when he was brought in by Graeme Souness.
Johnston had impressed at Celtic earlier in his career, scoring 52 goals in just 99 appearances for the Bhoys and he helped them win the league title before he left for French outfit Nantes in 1987.
His return to Glasgow two years later made headlines when he became just the second player to cross the Old Firm divide since World War II, following on from Alfie Conn in 1977, while he was the first openly Catholic player to sign for Rangers since World War I.
Johnston went on to win two Scottish league titles at Ibrox, scoring 46 goals in 100 games.
Forward Miller, meanwhile, had three separate spells at Rangers and also spent a year at Celtic in between.
Miller first joined Rangers in 2000 and scored eight goals in 30 appearances before making the move down south to Wolves.
He was then signed by Celtic in 2006, where he stayed for just a season, scoring seven goals in 33 games.
Miller then returned to Rangers between 2008 and 2011, scoring 49 goals in 81 games, before spells with Bursaspor, Cardiff City and Vancouver Whitecaps.
He returned to Ibrox again in 2014 for a final, lengthy four-year stay, this time hitting 35 goals in 114 games.
A less high-profile player to feature for both clubs was defender Pressley, who started his senior career with Rangers in 1990, making 34 appearances before joining Coventry City in 1994.
He made the switch to Celtic later in his career in 2006 but was only a bit-part player, making just 19 appearances across two seasons.
Pressley did, however, win the Scottish league title with both Rangers and Celtic.
The player to have made the most appearances in the Old Firm derby is Alec Smith, who played for Rangers between 1894 and 1913 and turned out in the famous clash a total of 87 times.
Next on the list is John Greig, who managed 75 appearances in the famous game between 1962 and 1978, also for Rangers.
Rangers legend-turned pundit Ally McCoist is the all-time leading goalscorer in the fixture with 26 goals in 55 matches in all competitions.
Robert Hamilton, who played for Rangers in two spells between 1897 and 1908, is second on the list with 24 goals in 46 games.
Celtic's record goalscorer in Old Firm games is Jimmy McGrory, who managed 22 goals in 35 derby matches, playing for the Hoops between 1922 and 1937.