Default font size

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>myPage</title>
</head>
<body>

myText

</body>
</html>

There is no designation of font size in the code above. in this case what size is for the font of “myText”?

The font size will be the default font size of the browser or whatever size the browser default has been changed to by the user.

Yup. Default size will vary by browser and user.
This is why you cant apply “print” logic to web design. The user has ultimate control of EVERYTHING including DEFAULTS AND preventing the user from being able to have control over such defaults is considered an accessibility FAIL.

What does that mean?
Would you rephrase the above, please?

Print logic: meaning that you have fixed or controlled dimensions.

For exaple, were I to be designing a poster for print … I could take for granted that a headline would not wrap… and since a non wrapping line of text looks good then that’s the solution.

Web design requires that you create solutions that work if the headline wraps or if it doesn’t.