Else

Else is primarily an adverb in English, used to refer to something other than what has already been mentioned, or to indicate an alternative or addition. Common constructions include what else, someone else, and elsewhere. In questions and negative statements, else conveys the meaning "otherwise." The term also appears in figurative phrases such as "elsewhere" or "what else can I do?"

In programming, else is a reserved keyword that introduces the alternative branch of a conditional. It is used with an if statement to specify code to execute when the condition is false. Common form in C, Java, JavaScript, and many languages: if (condition) { /* then */ } else { /* else */ }. Many languages also support an intermediate branch, else if (or elif), to test additional conditions. In Python the syntax is if condition: ... elif other_condition: ... else: ..., with indentation defining blocks. In switch statements, languages typically use a default clause instead of an else, to handle all remaining cases.

Notes: The presence and exact semantics of else can vary by language, particularly regarding short-circuit evaluation and side effects. The else block is optional; omitting it results in no alternate action when the if condition is false. Correct use of braces or indentation is important to avoid logic errors and mis-scoped blocks.