An acronym is when the first letters of words are used to formulate a word or expression. This new word or expression may create a new ‘real’ word or just some letters which are pronounced as one word or separate letters.
App (noun)
Pronounced as one word /æp/. This is something that you may have on a smartphone and is not referred to as an A.P.P. App is short for ‘application’ but in this context we do not say application. This can be used formally or informally.
FYI
‘For your information’.
FYI which is pronounced as a spelling F.Y.I and is more written than spoken and is definitely informal and only written in capital letters.
TTFN
Sometimes used as an ending in a text or email. In means ‘ta ta for now’. Ta ta is very informal speech to say ‘bye’
..for now, implies – see you later; probably soon.
OMG
Pronounced in speech as ‘Oh my god’. Informal and also used most likely in a text message or on social media to express a degree of shock. It is very common and may be accompanied by a symbol such as a smiley etc.
TMI
‘Too much information’ informal and now used either verbally or written. This is used when someone says more than they reasonably and politely expected to. Clear examples of this would be when someone says what they are going to do when they go the toilet! ‘I am going to the toilet’ is normally good enough. If someone says that they are going for a ‘poo’ people will often say either ‘too much information!’ or ‘TMI!’ said as a spelling rather than word.)
FYI
When spoken said as ‘For your information’ (formal/informal) or ‘F.Y.I’ in writing (informal).
This is normally used when we want to communicate something that is considered useful to someone.