Nielsen Norman GroupEvidence-Based User Experience Research, Training, and Consulting
Teens are (over)confident in their web abilities, but they perform worse than adults. Lower reading levels, impatience, and undeveloped research skills reduce teens’ task success and require simple, relatable sites.
When a multinational company produces a localized country site, usability is often lost. Local advertising agencies design good-looking sites that don't communicate.
If using web or browser-related terms, consider defining them in place to make websites easier for senior citizens. Avoid using technical words if they are not necessary.
User testing on 3 continents confirmed that the main usability guidelines hold worldwide, but many other considerations exist to better support international users.
Students are multitaskers who move through websites rapidly, often missing the item they come to find. They're enraptured by social media but reserve it for private conversations and thus visit company sites from search engines.