Understanding the substring(2, 4) Function in Programming

This snippet, 'substring(2, 4)', isn't a complete statement or function call. It's missing the closing parentheses, and the specific programming language or context isn't clear.

Assuming it's part of a function call in languages like JavaScript or Java, the 'substring' function extracts a portion of a string based on the provided starting and ending indices. In this case, the parameters '2' and '4' mean the returned substring starts at the 3rd character (index 2) and ends at the 4th character (index 3).

For instance, if the original string was 'hello world', 'substring(2, 4)' would return 'll'.