Generations of people throughout the Commonwealth and Australia have only ever known a world where Queen Elizabeth II reigned as monarch.
But with the Queen's passing and Charles becoming King, many of the royal symbols that have been so familiar to us for so long are about to change.
From the King's Counsel prosecuting criminal cases, to the Three Lions belting out a familiar anthem with slightly different lyrics, here's what you can expect to see change in the days and months ahead.
Courts
Criminal cases are typically initiated by the Commonwealth or state on behalf of the Crown.
This will continue to be the case, but there will be a few slight changes to wording to reflect the change of monarch.
Cases will now be brought forward in the name of his majesty, rather than her majesty.
And the "R" royal cipher used in court citations (eg. "R v Meloni") now refers to Rex rather than Regina.
Australian barristers who have been appointed as Queen's Counsel (or QC) will now be known as King's Counsel (or KC).
The change was made automatically upon the passing of the Queen, according to the Australian Bar Association.
Queen's Counsel did not need to seek new letters or take any further action to now act as King's Counsel, the association said.
Most states and territories now use the term Senior Counsel (or SC), but senior barristers in the Northern Territory, Queensland, Victoria and South Australia (and some in other states) are known as, or have the option to be known as, KCs.
The UK's anthem
The words to the British National Anthem will change slightly to reflect the change of monarch.
The anthem will be altered to God Save The King. This was the British National Anthem and the anthem of most Commonwealth realms up until the death of King George VI in 1952.
The lyrics to God Save The King at that time were:
God save our gracious King!
Long live our noble King!
God save the King!
Send him victorious,
Happy and glorious,
Long to reign over us,
God save the King.
The song was also Australia's national anthem before the readoption of Advance Australia Fair in 1984.
Coins and banknotes
Coins and banknotes bearing Queen Elizabeth II's effigy will remain legal tender and in circulation, but changes are afoot.
The Royal Australian Mint expects King Charles III to be on new Australian coins next year.
But the transition may take some time, and coins bearing the late Queen's effigy will continue to be minted and co-mingle in circulation with those showing the new sovereign.
The new coins will bear an effigy of Charles III facing left, in line with tradition which dictates that the direction the effigy faces changes with each new monarch.
In regard to banknotes though, the Reserve Bank of Australia says there will be "no immediate change" to $5 notes.
Passports
Among the legal documents we can expect to be changed following the accession of King Charles III are Commonwealth passports.
Australian passports specifically refer to "Her Majesty Queen Elizabeth the Second" on the first page inside.
The Prime Minister's office says the death of Queen Elizabeth II does not impact the validity of Australian passports.
Politics
MPs in the UK will have to swear a new oath to King Charles III before again sitting in the House of Commons as they have explicitly sworn allegiance to Her Majesty Queen Elizabeth.
Similarly, Victorian politicians will not be able to sit again in state parliament due to section 23 in the state's constitution, which requires them "whenever the demise of the Crown is notified" to take an "oath or affirmation to the successor for the time being to the Crown".
Victoria's parliament is due to sit again on Tuesday.
While Australia's Governor-General automatically becomes the representative of King Charles III following the death of the Queen, the same can't be said for many other members of the Commonwealth.
Many countries in the Commonwealth recognise Queen Elizabeth II specifically as head of state and their constitutions will need to be changed.
Countries such as Jamaica and Belize will most likely need to hold a referendum to change their constitution, opening the door to the possibility they could leave the Commonwealth.
