What does the 'i' flag stand for in a regular expression?global searchcase-insensitive searchmultiline searchUnicode search

In regular expressions, the 'i' flag stands for case-insensitive search. This means that when this flag is used, the matching process will ignore the case of the characters being searched. For instance, if you use the pattern abc with the 'i' flag, it will match not only "abc" but also "ABC", "AbC", "aBc", and any other combination of uppercase and lowercase letters.

Here’s a brief explanation of the other options you mentioned:

• Global search refers to the 'g' flag, which is used to find all matches in a string rather than stopping after the first match.
• Multiline search involves the 'm' flag, which allows the start (^) and end ($) anchors to match at the beginning and end of each line, not just the entire string.
• Unicode search relates to the 'u' flag, which enables support for matching Unicode characters.

In summary, the 'i' flag allows the use of regular expressions to find matches without considering the case of the text, making pattern matching more flexible and broad.