University of Illinois Urbana-Champaign

What are cookies?

Cookies are small text files that a website stores on your computer or mobile device when you visit the site.
They make your online experience easier by saving browsing information. With cookies, sites can keep you logged in, remember your site preferences and give you personalized content.
Cookies can also be used to establish statistics about the browsing experience and to show targeted ads.

What cookies are used on this site?

For the purpose of this site, we use Google Analytics (third-party cookies) to gauge site performance through browsing experience statistics. Allowing us to use these cookies helps us understand how visitors like you interact with our website and can help us figure out where we should focus our time and energy when making site improvements.

  • _ga (cookie used to distinguish individual users on the site, expires after 2 years)
  • _gid (cookie used to distinguish individual users on the site, expires after 24 hours)

How Google Analytics Uses Cookies


Cookies and other technologies used for analytics help collect data that allows services to understand how you interact with a particular service. These insights allow services to both improve content and build better features that enhance your experience.

Some cookies and other technologies help sites and apps understand how their visitors engage with their services. For example, Google Analytics uses a set of cookies to collect information and report site usage statistics without personally identifying individual visitors to Google. ‘_ga’, the main cookie used by Google Analytics, enables a service to distinguish one visitor from another and lasts for 2 years. Any site that implements Google Analytics, including Google services, uses the ‘_ga’ cookie. Each ‘_ga’ cookie is unique to the specific property, so it cannot be used to track a given user or browser across unrelated websites.

Google services also use ‘NID’ and ‘ENID’ cookies on Google Search, and ‘VISITOR_INFO1_LIVE’ and ‘YEC’ cookies on YouTube, for analytics."

Types of cookies

In general, cookies can be classified by:
1. Type:
– First-party cookies are issued by a website that a user views directly
– Third-party cookies are not created by the website being visited, but by a third party like Google Analytics, DoubleClick, Facebook, Twitter, LinkedIn, Youtube, Vimеo, etc.
2. Duration:
– Session cookies which is erased when the user closes the browser
– Persistent cookies which remains on the user device for a some period of time
3. Purpose:
– Strictly necessary cookies are required for the website to work properly
– Preferences cookies allow a website to remember choices you have made in the past
– Statistics cookies help website owner to collect statistic data and understand how visitors interact with website
– Marketing cookies track user’s online activity to help advertisers deliver more relevant ad. These are almost always third-party persistent cookies

Consent to use cookies

Many jurisdictions require that website owners obtain opt-in user consent before using cookies that are not strictly necessary. This is needed to be GDPR compliant and you give such consent when you click on the corresponding button of the cookie consent banner.
If you refuse, cookies will not be set.

How to manage cookie settings

Most web browsers allow you to manage your cookie preferences through the browser settings.

You can set your browser to refuse cookies, or delete all cookies.
Find out how to manage cookies on popular browsers:
Google Chrome
Mozilla Firefox
Apple Safari
Microsoft Edge
Microsoft Internet Explorer

Please note that if you choose to block cookies, this may impair or prevent due functioning of web pages.