quote (') - transpose operator, string delimiter
quote (')is used for (Conjugate) Transpose of matrix.
quote (.')is used for (non Conjugate) Transpose of matrix.
Simple (') or double (") quotes are also used to define character strings. (Character strings are defined between two quotes). A Quote within a character string is denoted by two quotes.
[1+%i, 2]' [1+%i, 2].' x='This is a character string' 'He said:''Good'''