Some abbreviations are read as individual letters:
– WHO (W-H-O) World Health Organisation IRA Irish Republican Army
– PLO Palestine Liberation Organisation UN United Nations
– BBC British Broadcasting Corporation PM Prime Minister
– ANC African National Congress MP Member of Parliament
In the following three cases, the name of each country and the name of its secret police are pronounced as individual letters/numbers.
– CIA (USA) MI5 (UK) KGB (former USSR, now CIS)
Note: When these abbreviations are stressed words in the sentence, the stress falls on the last letter, e.g. She works for the CIA. I heard it on the BBC.

Some abbreviations are read as words; we call them acronyms.

– NATO /’neitau/ North Atlantic Treaty Organisation
– OPEC /’aupek/ Organisation of Petroleum Exporting Countries
– AIDS /eidz/ Acquired Immune Deficiency Syndrome

Some acronyms have become so normal as words that people do not think of them as abbreviations any longer, and so they are not written all in capital letters.
– laser radar yuppy Esso

Some abbreviations are only written forms; they are still pronounced as the full word.
– Mr (Mister) Dr (Doctor) St (Saint or Street)

Abbreviations are used in the organisation of language.

– etc. /et’setra/ and so on [Latin: et cetera]
– i.e. (I-E): that is to say [Latin: id est]
– PTO (P-T-O) please turn over
– NB (N-B) please note [Latin: nota bene]
– RSVP (R-S-V-P) please reply [French: repondez s’il vous plait]
– e.g. (E-G) for example [Latin: exempli gratia]

Clippings: some words are normally used in an abbreviated form in informal situations.

– lab (laboratory) phone (telephone) fridge (refrigerator)
– TV or telly (television) board (blackboard) bike (bicycle) case (suitcase)
– exam (examination) plane (aeroplane) rep (business representative)
– ad/advert (advertisement) fax (telefax)

Some abbreviations you might see on a letter/fax/envelope.

– c/o care of [e.g. T. Smith, c/o J. Brown; the letter goes to J. Brown’s address]
– enc. enclosed [e.g. enc. application form]
– PS postscript [extra message after the letter has been ended]
– asap as soon as possible [e.g. ring me asap]