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Typography
📖 Typography · Module 1 of 6

Reading Type

Before you can choose a font, you have to learn to see one.

Anatomy · name the partsx-height · sets the voiceMobile · first, always

Most people look at a typeface and see only “text.” Designers see shapes — the height of an x, the openness of a counter, the cut of a terminal — and those shapes quietly decide whether a font is legible at 14px or falls apart.

This module hands you the vocabulary and the eye. Once you can name the parts, every later decision — pairing, sizing, setting — gets easier, because you finally know what you’re looking at.

01 · The Anatomy

The parts of a letter

The parts

Every letter is built on invisible lines — the baseline it sits on, the x-height the lowercase reaches, the cap height of the capitals, and the ascenders and descenders that poke above and below. The enclosed white shapes (the hole in an o) are counters; the ends of strokes are terminals.

These aren’t trivia. They’re the levers a type designer pulled — and the features you read to predict how a font will behave. Find them below.

The Anatomy Explorer
Tap a part to find it on the letters. (Lines are illustrative — exact metrics vary by font.)
Ascender
Cap height
x-height
Baseline
Descender
hago
Tap a part above to highlight where it lives on the letterforms.
02 · Classification

The five families

The families

Typefaces sort into a few broad families, and each carries a default voice. You don’t need the full history — you need to recognise them on sight and know what each tends to say.

Ag
Serif
classic, trusted
Ag
Sans
clean, modern
Ag
Mono / Slab
technical, exact
Ag
Script
warm, personal
Ag
Display
loud, headline-only
Serif and sans do the heavy lifting for text. Script and display are seasoning — powerful in a headline, painful in a paragraph.
03 · Legibility

Why x-height rules small sizes

Why it matters

Here’s the single most useful thing anatomy teaches: two fonts at the same point size can look completely different sizes, because the lowercase letters — the ones you actually read — can be tall or short relative to the capitals.

A tall x-height with open counters stays clear and roomy at 14–16px, which is why interface fonts have them. A low x-height looks elegant large, but muddies and shrinks at body sizes.

Same size, different size
Both letters are set at the exact same point size. Watch the lowercase, not the cap.
Rx
Inter · tall x-height
Rx
Playfair · low x-height
Identical point size — yet Inter’s x reads larger and clearer. At 14px that difference is the line between effortless and squinting.
Same size, different  font
All three set at the identical size — yet each speaks in a different voice.
Ag
Inter · clean, modern
Ag
Lora · warm, editorial
Ag
Mono · technical, exact
Same size, same letters — three personalities. Size sets how big; the font sets how it feels.
Seen in the wild

Anatomy, chosen on purpose

Two products, two deliberate anatomical choices — each fits the job it does.

SaaS dashboard
Monthly revenue +12.4%
Active users 8,201
Churn 1.2%
Tall x-height, open counters

An interface face like Inter stays crisp at 14px in dense data — the lowercase never closes up.

Editorial
The Long Read
where letters can be elegant
Low x-height, high contrast

A face like Playfair is gorgeous large, where the delicate strokes and modest x-height read as refinement, not strain.

Where anatomy meets the other forces

Anatomy is the foundation the other modules build on. A tall x-height lets you use a smaller size and still read — changing your scale. Open counters survive a heavier weight without clogging — changing your hierarchy. You can’t set, size, or pair type well until you can see the shapes underneath.

The vocabulary

The Anatomy glossary

Six words that turn “it looks off” into a diagnosis. Tap a card to flip it.

The nuance

Questions you actually ask

Train the eye

Name the part

Ten questions in seven formats — multiple choice, multi-correct, fill-in, match, order, read-think-connect and write-your-own — each with layered hints: a nudge, the reasoning, then a deeper connection. Served from the question bank, never hardcoded.

Loading the question bank…
Question 1 of 10
Multiple choice
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Where this connects