dataLayer.push({    });

dataLayer.push javascript snippet is used to push details to Google tag manager. We can create a event and variables required for this/

dataLayer.push({
‘event’:’Scrollview’,
‘pageurl’:titleurl,
‘pagetitle’:title
});

Here we creating  an event called “ScrollView” , pageurl and pagetitle are variables we need to push to tag manager.

Using these variable and event we need to configure an event in google tag manager console.