what is difference between single inverted and double inverted in programming languages code example

Example: what is difference between single inverted and double inverted in programming languages

[...] In common usage, there may be a distinction between the
single and double quotation marks in this context; often, single
quotation marks are used to embrace single characters, while 
double quotation marks enclose whole words or phrases[.]


Simply: according to the charcter check for string and char
1. if char , then use '';
2. if string , then use "";