An honorific is a title that conveys respect when used to address a person. The most common are Mr and Mrs. Master is now rarely used for a boy.
Miss, for a single woman, is gradually being replaced by Ms, which indicates a woman who is either married or not.
A new honorific is Mx, (pronounced Mix or Max) which indicates a person regardless of gender, for those who do not wish their gender to be revealed. It might have been useful in the past for female authors, such as George Eliot or the Brontë sisters, who instead had to use a male name in order to be taken seriously.
As well as gender and marital status, an honorific can indicate an occupation, such as Doctor, Captain, Officer, Reverend, or Professor. They can either precede a surname or stand alone.
Other stand-alone titles are Sir, Ma’am or Your Honour (to a judge). Family relationships are used as titles, such as Brother (monk or friar), Father (priest), or Mother (Mother Superior in charge of a convent). Sister can refer to a nun or a nursing sister. The title of Matron, the person in charge of all the nursing staff of a hospital, was changed to Chief Nursing Officer. Recently, the British Government announced the return of the matron to the NHS.
In most countries, physicians, surgeons, GPs etc are called Doctor. The exception is surgeons in the UK.
Historically, while physicians needed a medical degree to practise medicine, a surgeon only needed a diploma and was known only as Mr, not Dr.
Today, surgeons take the same path as physicians via extensive study, university or medical school degrees, before becoming a consultant surgeon, so they start as a Mr or Ms, become a Dr and then revert to Mr or Ms again.
Titles used in Europe derive largely from the ancient world. Sir comes from the Latin seniorem meaning ‘elder’, the same source as Sire and the Spanish titles Señor, Señora, Señorita, the Portuguese Senhor, the French Monsieur and the Italian Signor. Ma’am comes from the Old French Ma dame ‘my lady’.
Religious titles and royal titles can be tricky to get right, but other cultures are more complex. Asian cultures such as Japanese and Korea have complex systems of titles. Italian uses professional titles such as Ingegnere ‘engineer’ in place of Signore.
Some foreign honorifics we are familiar with are the Sanskrit title Mahatma ‘great soul’ applied in India to prominent people such as Gandhi, and Dalai Lama, the title given to the spiritual leader of Tibetan Buddhists, currently held by Tenzin Gyatso.
In Spain Maestro is used as a term of respect for artistic masters and Don and Dona for people of rank. The only group of people I can find that don’t use titles are the Quakers, who address each other by name only, or ‘brother’, ‘sister’ or ‘friend’, due to their strong sense of egalitarianism.