Research into the UK's email habits has revealed that people's biggest complaint is the overuse of capital letters in messages.

The study of 3,000 email users by peripherals firm i.Tech Dynamic has revealed the top five email gripes as:

The research also threw up some interesting views on fonts. Two thirds of bosses indicated that they would not interview a candidate if they did not like the font of their CV, and 80 per cent of bosses would confront a co-worker if they used a font they did not like.

"Email is such a massive part of our lives nowadays and we do get set in our ways when it comes to things like fonts and the etiquette of writing at work," said a spokesman for i.Tech, which conducted the research as part of its development of a Bluetooth keyboard.

"People should be aware that some fonts are too elaborate for professional documents, not to mention hard to read. If you stick to the basic fonts and in a reasonable size and colour you should be pretty safe and not offend anyone."

Britain's most popular font is Arial 12 point in black, although five per cent of people type in purple or pink. Eighty per cent of those questioned think it is inappropriate to use elaborate fonts in work emails.

Nearly three quarters of those questioned found 'kisses' at the end of emails annoying, but a quarter of the women questioned used them.

Three quarters of women said they would type in a different font if they were writing a love letter, but only half of men would bother.