- In an article, an h1 is the same size as an h2
- It is invalid to have an h1 tag in an article. If you do this the
validator gives a warning. You should use h2-h6 tags.
- Despite being part of w3c's HTML5 specifications, the
<bdi> tag is not supported by all browsers
- Images must have an
alt attribute. This is not considered optional or an accessibility feature.
<b> tag and <strong> tag, <i> tag and <em> tag have the same effect on the web browsers.
<b> tag and <i> tag are explicit. <strong> tag and <em> tag are semantic. <input> tags without a name attribute will not send their data when their parent form is submitted. However, they are still valid HTML tags and errors can slip under the radar this way.- The
<button> tag will by default act as a submission button. This can be avoided by explicitly setting the type attribute to some other legal value. Interestingly, both the <button> and <input> tags behave the same when using the type="button" attribute.
- If you use a javascript function with the same name as your html event handler attribute it will not work. For example if you want to handle an onblur event with a function called onblur() or blur() it won't work.
But this seems to be case sensitive as well ie Blur() and onBlur() seems to work fine.
- If you handle an onfocus event with an alert it will continuously fire the event, such that you get that same alert continuously.
- HTML tags which affect look-and-feel are essentially useless, as CSS is a thing that exists.
Click to see this page's HTML validation results.