### How it works
-Here's a rundown of how form validation works:
+Here's how form validation works with Bootstrap:
-- HTML form validation includes support for two CSS pseudo-classes, `:invalid` and `:valid`, on `<input>`, `<select>`, and `<textarea>` elements.
-- Due to constaints in how CSS works, we cannot (at present) apply styles to a `<label>` that comes before a form control in the DOM without the help of custom JavaScript.
+- HTML form validation is applied via CSS's two pseudo-classes, `:invalid` and `:valid`. It applies to `<input>`, `<select>`, and `<textarea>` elements.
- Bootstrap scopes the `:invalid` and `:valid` styles to parent `.was-validated` class, usually applied to the `<form>`. Otherwise, any required field without a value shows up as invalid on page load. This way, you may choose when to activate them (typically after form submission is attempted).
-- As a fallback, `.is-invalid` and `.is-valid` classes are available for [server side validation](#server-side) (without the need for a `.was-validated` parent class).
+- As a fallback, `.is-invalid` and `.is-valid` classes may be used instead of the pseudo-classes for [server side validation](#server-side). They do not require a `.was-validated` parent class.
+- Due to constaints in how CSS works, we cannot (at present) apply styles to a `<label>` that comes before a form control in the DOM without the help of custom JavaScript.
- All modern browsers support the [constraint validation API](https://www.w3.org/TR/html5/forms.html#the-constraint-validation-api), a series of JavaScript methods for validating form controls.
-- Feedback messages may utilize the browser defaults (different for each browser, and unstylable via CSS) or our custom feedback styles with additional HTML and CSS.
+- Feedback messages may utilize the [browser defaults](#browser-default) (different for each browser, and unstylable via CSS) or our custom feedback styles with additional HTML and CSS.
- You may provide custom validity messages with `setCustomValidity` in JavaScript.
-With that in mind, consider the following two demos for our custom form validation styles and browser defaults.
+With that in mind, consider the following demos for our custom form validation styles, optional server side classes, and browser defaults.
### Custom styles