HTML <TT> (Teletype) Element
The content of a <tt> element is written in monospaced font (like that of a teletype machine).
<tt> is short for teletype, and instructs the browser to render the text similar to that produced by old-style teletype machines, which is understood to be a fixed-width (monospace) font.
the following word will appear in <tt> monospaced</tt> font.
HTML <kbd> Element.
The <kbd> element is used for text typed on a keyboard. If when talking about a computer, you want to tell a reader to enter some text, you can use the <kbd> element to indicate what should be typed.
<p> The shortcut key for bold the text <kbd>ctrl</kbd>and<kbd>b</kbd> </p>
You can see above the word ctrl and b are displayed in monospaced font after using <kbd> element. The content of the <kbd> element is usually represented in a monospaced font, rather like a <code> element.