Cookies are small data files that websites store on a visitor’s device to remember information about them. They play a big role in enhancing user experience, personalizing content, saving login details, and even tracking behavior across different websites.

In the world of website design and development, cookies are essential tools used to collect and store data that help improve functionality and client engagement. From remembering language preferences to enabling auto-fill forms and personalized ads, cookies are used in all kinds of ways to make sites more user-friendly and efficient.

How do cookies work in website design?

Cookies work by storing bits of information directly on a user's browser. When someone visits a site, the server sends a cookie to their device. The browser then saves this data and sends it back to the server every time the visitor returns. This makes things like login sessions, shopping carts, and personalization possible.

For example, when a user logs into a member-only area of a site and checks “remember me,” a cookie store that session data. This way, the user doesn’t have to log in every time.

Cookies can also support your SEO strategy by helping track user engagement and behaviors, which informs website improvements and marketing strategies.

Types of cookies

Session cookies

These are temporary and get deleted once the user closes their browser. They're useful for things like shopping cart data that only need to last for a single session.

Persistent cookies

These stay on a user’s device even after the session ends. They're used to remember login info, preferences, and customized settings.

Third-party cookies

These are set by a different domain than the one the user is visiting. They’re mostly used for advertising and tracking across different websites.

Essential vs. non-essential cookies

Essential cookies are necessary for a site to function (like login authentication). Non-essential ones include things like analytics and targeted advertising.

Why cookies matter in web design

Cookies help AI website builders deliver personalized and intuitive user experiences. By collecting behavioral data, they allow websites to serve more relevant content, increase client engagement, and optimize how a site functions based on actual user interaction.

They also play a role in analytics tools, enabling web teams to fine-tune designs and better understand what’s working and what needs improvement. For business owners, this can translate to better conversions, more time spent on-site, and an easier path to building trust with visitors.

Some AI Assist-driven platforms use cookies to improve tools like automated content creation or email marketing campaigns by learning from how visitors engage with content.

FAQs about cookies in website design

What information do cookies store?

Cookies can store data like usernames, session IDs, language preferences, items in a shopping cart, and analytics data like how long you stayed on a page. They don't typically store sensitive personal info unless you’ve entered it and the site is designed to retain it.

Can users block or delete cookies?

Yes. Users can disable or delete cookies in their browser settings. Most modern websites now also have cookie consent banners to let users opt in or out of certain cookie types.

Are cookies safe?

Generally, yes. Cookies themselves can’t run code or carry viruses. However, they can be used maliciously for tracking or data collection if not managed properly. That’s why sites should follow privacy regulations like GDPR or CCPA.

Do cookies impact website speed?

Not significantly. Cookies are small in size and usually have minimal effect on load times. However, if a site uses a large number of third-party cookies, it could slightly slow down performance.

How do I know if my website uses cookies?

You can use browser tools (like the developer console) or online cookie scanners to check if and which cookies your site is using. Website builders like B12 often include cookie notifications and settings by default.

What you should take away from this

Cookies may be small, but they have a huge impact on how users interact with your website. From keeping track of login sessions to helping with personalized marketing and online scheduling, they’re an important part of designing a seamless experience.

For anyone building or managing a website, especially with the help of tools like B12, understanding cookies can help you stay informed, improve user satisfaction, and remain compliant with privacy standards. Whether you're managing a small blog or launching a new business site, this knowledge is something you’ll use time and time again.

Ready to build a site that uses cookies the smart way? Get started today.