What distinguishes a class selector from an ID selector in CSS?

A class selector in CSS is designed to apply styles to multiple elements that share the same class name, making it a powerful tool for maintaining consistent styling across similar elements without duplicating code. By using a class selector, you can group various elements and apply a common set of styles, enabling flexibility and efficiency in your web design.

On the other hand, ID selectors are meant to be unique and should only be applied to a single element within a page. This ensures that each element identified by an ID can be targeted specifically without the risk of overriding styles in other instances.

Therefore, the distinction lies in the purpose and usage: class selectors are intended for multiple elements sharing the same class, facilitating easy management of styles, while ID selectors are specific to a single instance, reinforcing their uniqueness on the page.