HTML tags showed up in email message

Guys: I wrote a mail script in PHP to allow users to compose email messages. I highlighted some text with HTML, for example, I did:

<strong>Subject: </strong>

But when users received an email from the system, they did not see

Subject:

Instead, they saw raw HTML tags

<strong>Subject: </strong>

The HTML tags were still there and did not really apply to the text.

I’m wondering if I missed anything in the headers or MINE type or something. Any idea ? Thanks.

Have a read of the following article by Chris Coyier http://css-tricks.com/sending-nice-html-email-with-php/

Thanks Chris.