From Wiktionary, the free dictionary
{ } English symbol name curly brackets or braces
( mathematics ) Encloses a mathematical phrase which has increased operator precedence. Synonyms: ( ) [ ] 10/2+3 = 5+3 = 8 10/{ 2+3} = 10/5 = 2 ( mathematics ) fractional part .
{3.14} = 0.14 ( set theory ) Encloses a set. Set of positive divisors of 6 = { 1, 2, 3} . The set of even numbers can be written as { n ∊ ℤ : ∃ k ∊ ℤ: n = 2k } . ( set theory ) Set of natural numbers between 2 and 3 = { } . Alternative form: {} Synonym: ∅ ( programming ) Used in some programming languages , especially C-type languages. Encloses the body of a function . doSomethingTwice () { return doSomething () + doSomething () }
Encloses each branch of a conditional . if (x>4) { result = "congratulations!" }
{ }
Encloses a series of equal choices . Select your animal { goat, sheep, cow, horse} and follow me. ( phonology ) Encloses morphophonemic transcription; especially when presented as sets of phonemes rather than as single symbols for archiphonemes . Synonyms: ⫽ ⫽ | | ‖ ‖ Coordinate terms: / / [ ] ⟨ ⟩ ⸢ ⸣ ! ! \ \ We can write la{ t,d} er for the conflated pronunciation of ladder and latter in American English. This may instead be written ⫽laDer⫽, where ⫽D⫽ is the archiphoneme { t, d} , or with both conventions for { laDer} .( phonetics ) VoQS notation.( papyrology, epigraphy ) Encloses writing by the original scribe that the editor considers erroneous. 
