For HTML5, the HTML tags and attribute names are case-insensitive, which means that you can mix the cases. Modern browsers like Google Chrome and Mozilla Firefox will automatically parse all your HTML tags and attribute names to lowercase.
Read moreWhat is case insensitive in Python?
Case-insensitive means the string which you are comparing should exactly be the same as a string which is to be compared but both strings can be either in upper case or lower case . ( ie., different cases)
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