performance

Below roughly 400 milliseconds of system response, people stop waiting on the machine and productivity rises sharply.

LAW·006Law · Performance

Absorbed, effortless concentration occurs when challenge and skill are balanced, and interruptions destroy it.

PSY·005Psychology · Engagement

Interface typefaces are chosen for legibility at small sizes and complete character coverage, not for character.

FND·030UI foundation · Typography

One file containing a continuous range of weights and widths, usually smaller than the static weights it replaces.

FND·037UI foundation · Typography

Simulated light, which reads as physical only when it follows one consistent light source.

FND·049UI foundation · Form and depth

Images either carry information or they do not, and the ones that do not are costing you load time.

FND·051UI foundation · Form and depth

Animation should explain a change, and anything that does not explain something is delay.

FND·052UI foundation · Form and depth

Suggestions as the user types, which turns recall into recognition when it is fast enough.

PAT·003Pattern · Finding

What to show while waiting, chosen by how long the wait is and whether its length is known.

PAT·011Pattern · Content states

Apply the change immediately and reconcile with the server afterwards, so the interface never waits on the network.

PAT·013Pattern · Content states

Three ways to handle long result sets, each with a different cost, and the right choice depends on the task.

PAT·021Pattern · Finding

Making content findable by search engines, which overlaps almost entirely with making it good for people.

WRT·007UX writing · Content

Say what is happening, how long it will take if you know, and whether it is safe to leave.

WRT·011UX writing · UX writing

Speed is a usability property, and the metrics that matter are the ones measured on real devices.

FND·054UI foundation · Performance

Touch targets, reach, input, performance and the assumptions that only fail on a phone.

CHK·003Checklist · Mobile

The pass before shipping, covering states, edge cases, accessibility, performance and the things that only break in production.

CHK·009Checklist · Release

A review pass for anything that lives at a URL: addressability, navigation, performance, content and the browser behaviours people expect.

CHK·011Checklist · Web

Built into Chrome, covering performance, accessibility, SEO and best practices in one run.

TOOL·031Tool · accessibility

Detailed performance testing from real devices and locations, with filmstrips that show what the page looked like while it loaded.

TOOL·032Tool · testing