To continue last month's investigation of pseudonyms, we can add further reasons why people adopt new names for themselves. When many artistic Europeans emigrated to the USA, they anglicised their names or changed them to more acceptable pseudonyms.

Samuel Gelbfisch from Poland was anglicized to Samuel Goldfish by the immigration authorities but evolved into the famous film producer Sam Goldwyn. The Russian-born composer Israel Baline became Irving Berlin; Jacob Gershovitz was translated into George Gershwin; and the French-born singer Alice Joséphine Pons turned into Lily Pons (with a hint of a pun on "lily ponds").

Entertainer Asa Yoelson changed into Al Jolson, and Borge Rosenbaum became Victor Borge. Actor Issur Danielovitch Demsky, the son of Russian-Jewish parents, chose the name Kirk Douglas - Kirk because it sounded "snazzy" and Douglas because he admired Douglas Fairbanks.

The same process occurred on a smaller scale in Britain, with Paul Hamburger becoming the publisher Paul Hamlyn, Louis Winogradsky turning into Lew Grade, and Jan Ludvik Hoch becoming Robert Maxwell..

A lot of musicians alter their names - especially in the world of pop music. Tommy Hicks became Tommy Steele; Reginald Smith became Marty Wilde; Roy Taylor became Vince Eager; and Ron Wycherly became Billy Fury.

If you notice some similarities in these names, it is because they were all bestowed on the singers by Larry Parnes, a very successful British agent who seemed determined to give pop performers more sexy or striking names. He was nicknamed "Mr Parnes, Shillings and Pence" because of his reputed meanness towards his artists.

Parnes even wanted to change Joe Brown's name to Elmer Twitch, but Joe resisted. Nonetheless, Parnes was responsible for a slew of pop pseudonyms in the 1950s and 1960s, including Duffy Power, Lance Fortune and Johnny Gentle. Under Larry Parnes's guidance, Lancashire organist Clive Powell became Georgie Fame.

Other agents also bestowed pseudonyms on performers. Declan McManus was given the name Elvis Costello after Elvis Presley and Costello, the name used by Declan's father when performing as a singer.

Peter Gammond's Oxford Companion to Popular Music (1991) tells how the French singer Edith Giovanna Gassion "was befriended by Louis Leplée, owner of the well-known Cerny's cabaret, who gave her the nickname piaf' (Parisian slang for sparrow') because of her diminutive size and chirpy appearance."

Many pop stars chose their own pseudonyms. Reg Dwight adopted the name of Elton John from the first names of jazz-rock saxophonist Elton Dean and rock singer Long John Baldry. Terence Nelhams chose Adam Faith from a book of names for children: Adam from the boys' section and Faith from the girls' lists. Robert Zimmerman became Bob Dylan as a tribute to the Welsh poet Dylan Thomas.

In the 1920s, a music hall entertainer named Vernon Watson found inspiration for his pseudonym Nosmo King from a No Smoking sign.

Some entertainers adopt pseudonyms because their real names sound demeaning or even embarrassing. This happened with Jeannie Carson (real name Jean Shufflebottom), Diana Dors (Diana Fluck), Joanne Dru (Joanna La Cock), Marti Caine (Lynda Crapper) and Lois Maxwell (Lois Hooker). John Wayne was undoubtedly glad to have his screen name, as his real name - Marion Morrison - was scarcely suitable for a hero of Western films. Another movie cowboy, Roy Rogers, understandably changed his name from Leonard Slye.

During the First World War, the British royal family changed its name to the House of Windsor, as the Germanic-sounding Saxe-Coburg-Gotha was undoubtedly embarrassing when we were at war with Germany. The name Windsor was also adopted by Barbara Windsor, whose real name was Barbara Anne Deeks. She said "I'm very, very pro-royal."

Some pseudonyms get chosen very casually. When John Ravenscroft was starting as a disc jockey for Radio London, a typist suggested "Why don't you call him John Peel?'"

In the film world, many pseudonyms are created by agents, producers and the like. Roy Fitzgerald was renamed Rock Hudson by a talent scout - from the Rock of Gibraltar and the Hudson River. Norma Jean Baker was turned into Marilyn Monroe by a casting director. Bernard Schwartz was given his pseudonym Tony Curtis by a film producer who said: "Schwartz ain't a name to get you into the big time."

Yet other film stars selected pseudonyms for themselves. Arthur Stanley Jefferson was happy with his stage name of Stan Jefferson until he realised it contained 13 letters, when he changed it to Stan Laurel. William Claude Dukinfield became W C Fields but also used a host of pseudonyms including Otis Criblecoblis, Mahatma Kane Jeeves and Egbert Souse.

If you see the name Alan Smithee in the credits for a film, it is a pseudonym used by directors and others who do not wish to be associated with a film that they worked on. The 1969 movie Death of a Gunfighter had two directors who were both unhappy with the film, so the credits said that it was directed by Alan Smithee. The name David Agnew in the credits for British TV programmes is a similar pseudonym, while Walter Plinge is used in the theatre to disguise an actor who wants to remain anonymous. There was reportedly a real Walter Plinge, a London pub owner.

Tony Augarde is the author of The Oxford Guide to Word Games (OUP, £14.99) and The Oxford A to Z of Word Games (OUP, £4.99).