---
title: What is a cookie? 🍪
slug: what-is-a-cookie
docTags: 
createdAt: 2024-10-25T15:14:17.861Z
---

A cookie is a Google Sheet thats tied to your browser and website. Thats it. Originally, they were meant to help with authentication. So the google sheet for your site might look a little like this:

| Name       | Value                                                                |
| ---------- | -------------------------------------------------------------------- |
| login\_key | f3h3948fgniouiun3rgiufrn3uignfiu3erngfuinuig3nuirnguiniugenuirnguini |

That weird combination of letters and numbers would be something like a temporary password thats used to get stuff from the website (like your credit card numbers, or your name and such).&#x20;

That aside, cookies these days are mainly used for tracking. As mentioned before, the pixel code tends to create 2 cookies, a ***browser id&#x20;***&#x63;ookie and ***click id&#x20;***&#x63;ookie. The first one, the browser id, identifies the browser thats making the request. Its how they can connect multiple events. So if you visit the homepage, then the about us page, the do a purchase? They connect those dots with the browser id.&#x20;

The click id, in contrast, is an identifier that shows up ***after&#x20;***&#x79;ou click an ad. So the url after clicking on an ad in Facebook will look a little like this:

:::hint{type="info"}
https\://www\.datus.cloud/?**fbclid=rgwu3gnfiun3gewuifnr3uiegfnuiwe43**
:::

That "**rgwu3gnfiun3gewuifnr3uiegfnuiwe43**" value identifies you on Facebook's *own system*. So if they have that send to them when you make a purchase? Thats ***exactly&#x20;***&#x77;hat they want.

So presumably, if you visited a website that has a Facebook pixel ***after&#x20;***&#x63;licking an ad on facebook your cookies would look a little like this:

| Name            | Value                                                            |
| --------------- | ---------------------------------------------------------------- |
| login\_key      | f3h3948fgniouiun3rgiufrn3uignfiu3erngfuinuig3nuirnguiniugenuirng |
| fb\_browser\_id | browser\_ohnrw3fgo                                               |
| fb\_click\_id   | rgwu3gnfiun3gewuifnr3uiegfnuiwe43                                |



With those cookies there, whenever the pixel sends an event to facebook? It sends the cookies.
