The reason why "1st Party Cookie", "Custom JavaScript", "Data Layer Variable", and "JavaScript Variable" are under page variable in Google Tag Manager is because they are all related to the page that the tag is firing on.
"1st Party Cookie" is a cookie set by the website itself and can be used to track user behavior or remember user preferences on the website.
"Custom JavaScript" allows you to add your own custom JavaScript code to the page, which can be used for various purposes like tracking events or modifying the page content.
"Data Layer Variable" is a variable that gets its value from the data layer, which is a JavaScript object that contains information about the user's interaction with the website.
"JavaScript Variable" is a variable that gets its value from a JavaScript code on the page.
All of these variables are related to the page and can be used to capture information about the user's interaction with the website or to modify the page content based on that interaction. Therefore, they are categorized as page variables in Google Tag Manager.
