What it means
A family can carry an entire website without needing several unrelated typefaces. Headings, labels and body copy can share the same letterforms while changing weight and scale. In CSS, a font-family declaration also lists alternatives in order, which is a font stack rather than a single designed family.
Use it in practice
Choose a family with enough range for your real content. Check whether italic, numerals and language support are available before committing.
Watch out for
More weights do not automatically make a stronger hierarchy. Give each style a clear role.
