to provide ad delivery or retargeting.

to store account details.

to store and track if the browser tab is active.

to store browser details.

to provide fraud prevention.

to store a unique user ID.

to provide fraud prevention.

to store and track visits across websites.

to Store logged in users.

to provide ad delivery or retargeting.

to read screen resolution.

to store a unique session ID.

to store account details.

to store last visit.

to store user preferences

to store and track visitor journeys through the site and classifies them into groups.

to store and track visits across websites.

to store number of service requests.

to store and count pageviews.

to Provide parameters to URLs to identify the campaigns that refer traffic.

to Provide parameters to URLs to identify the campaigns that refer traffic.

Thrown when a redirect experiment is running. Stores the experiment ID, variation ID, and referral source to the redirected page.

Retains the last query parameter utm_campaign.

Used for campaigns linked to Google Ads Criteria IDs.

Used for campaigns associated with Google Ads ad group IDs.

Used for campaigns linked to Google Ads Campaign IDs.

Used for campaigns that are linked to Google Ads customer IDs.

Determines when the experiment in which the user participated expires.

Determines if the user took part in the experiment.

Stores data about a visitor level custom variable. Thrown when a developer uses the _setCustomVar method with a visitor-level custom variable. Also used by the _setVar method, which is no longer supported. Updated every time data is sent to Google Analytics.

Stores information about the source of traffic or campaign, allowing you to understand where the user came to the site from. Generated when the library is run and updated every time data is submitted to Google Analytics.

Not used in ga.js. Installed for interoperability with urchin.js. Previously worked in conjunction with the __utmb cookie to determine whether a user should start a new session or visit.

Used to define new sessions / visits. Thrown when the JavaScript library is executed if there are no existing __utmb cookies. Updated every time data is sent to Google Analytics.

Limits the frequency of requests.

Allows you to distinguish between users and sessions. Thrown when the JavaScript library is executed, if there are no existing __utma cookies. Updated every time data is sent to Google Analytics.

Contains a token that can be used to get the Client-ID from the AMP service. Other possible values: disabling the function, active request, or an error in obtaining the Client-ID from the AMP service.

Allows you to differentiate between users.