What is Google click id?

Gclid, also knows as a “Google Click ID” , Google Click Identifier,” and “auto-tagging” is a tracking identifier that is generated when someone searches one of your targeted keywords and clicks on your google ad. Every time your ad gets clicked on through Google Ads, a Gclid will be added to the end of the link.
 

Why Use Google click id?

Google Click ID passes data from your Google Ads account to your Google Analytics account automatically, without having to create multiple, lengthy URLs. Enabling a Gclid will save you time and track the campaign, cost-per-click, sessions, bounce rate, ad group targeting, keyword targeting, which ad was driving clicks, and conversion data.