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CSS How to Make a Website Beginning HTML and CSS Introduction to HTML and the Portfolio Project

Posted by S.M.Mohieminul Hossain
S.M.Mohieminul Hossain
3,329 Points

HTML Tag

Are html tags case sensitive?

3 Answers

Ted Sumner
PLUS
Ted Sumner
Courses Plus Student 17,967 Points
Ted Sumner
Ted Sumner
Courses Plus Student 17,967 Points

Dave your example is true, but I think misleading. HTML is case sensitive, but in your markup your open and closing tags are all the same case and thus follow the case sensitive rules. A capital letter is not the same as a lower case letter.

<!-- This is valid markup -->
<Body>code here</Body>

<!-- This is NOT valid markup -->
<Body>code here</bOdy>
<body>code here</Body>
<BODY>code here</body>

HTML, CSS, PHP, and CSS are all case sensitive. This != this.

And case matters in the Treehouse quizzes. One of the early quizzes rejects Javascript because the proper answer is JavaScript.

S.M.Mohieminul Hossain
S.M.Mohieminul Hossain
3,329 Points

Thank you Ted

Petar Popovic
PLUS
Petar Popovic
Courses Plus Student 23,421 Points
Petar Popovic
Petar Popovic
Courses Plus Student 23,421 Points

Yes, they are :)

S.M.Mohieminul Hossain
S.M.Mohieminul Hossain
3,329 Points

Thank you Petar

Dave Berning
Dave Berning
17,365 Points
Dave Berning
Dave Berning
17,365 Points

HTML tags are NOT case sensitive; they are case INsensitive. You can mix and match which case you use when writing your markup.

<!-- This is valid markup -->
<h1>Treehouse Blog</h1>

<!-- This is also valid markup -->
<H1>Treehouse Blog</H1>

However, it's best practice is to use all lowercase. Using all caps is frowned upon and terrible for readability.

Programming languages like JavaScript are definitely case sensitive ;)

S.M.Mohieminul Hossain
S.M.Mohieminul Hossain
3,329 Points

Thank you Dave