# Cloudflare

> A global network that sits in front of websites to make them faster and safer.

- Level: Basic
- Topics: Tech companies, Networks
- URL: https://tidbit.legios.com.ar/cloudflare/
- In Spanish: [Cloudflare](https://tidbit.legios.com.ar/es/cloudflare/)

**Cloudflare** is an American company founded in 2009 by Matthew Prince, Michelle Zatlyn and Lee Holloway. It runs a network of data centers in cities all over the world, and websites put it **in front of** their own servers. When you visit a site that uses Cloudflare, your request first reaches the Cloudflare data center closest to you, not the site's real server, which is called the **origin**.

From that position it can do several jobs at once. It works as a CDN, keeping copies of images and pages near visitors so they load faster. It absorbs DDoS attacks, where floods of fake traffic try to knock a site offline, and filters malicious requests with a firewall. It also handles the site's HTTPS certificates and its DNS. Beyond websites, it offers **Cloudflare Workers**, which run small programs in its data centers, close to users, and the public DNS service `1.1.1.1`.

Its business model is freemium: a basic plan is free, which is why millions of small sites use it, and companies pay monthly for more features or sign larger contracts. The flip side of being in front of so much of the web is that when Cloudflare has an outage, many unrelated sites and apps fail at the same moment.

## An analogy

A front desk with a security guard for a building. Visitors check in at the lobby, the guard turns away troublemakers, and common questions get answered right there without bothering the people upstairs.

## Keep in mind

- Founded in 2009; runs data centers in cities around the world.
- Sits between visitors and a site's origin server, acting as CDN, shield and DNS.
- Free basic plan; companies pay for advanced features and contracts.
- Because so many sites rely on it, its outages are felt across the web.

## Go deeper

- [About Cloudflare (official site)](https://www.cloudflare.com/about-overview/)
- [Cloudflare developer docs](https://developers.cloudflare.com/)
- [Cloudflare on Wikipedia](https://en.wikipedia.org/wiki/Cloudflare)

## Related terms

- [Data center](https://tidbit.legios.com.ar/data-center/): A building full of servers where the internet, the cloud and AI actually run.
- [Server](https://tidbit.legios.com.ar/server/): A computer whose job is to answer requests from other computers, all day, every day.
- [CDN](https://tidbit.legios.com.ar/cdn/): Copies of a website kept on servers around the world, close to whoever asks.
- [DDoS](https://tidbit.legios.com.ar/ddos/): Knocking a site offline by flooding it with more traffic than it can handle.
- [Firewall](https://tidbit.legios.com.ar/firewall/): A gatekeeper that decides which network traffic gets in or out.
- [HTTPS](https://tidbit.legios.com.ar/https/): The padlock in your browser: web traffic nobody in between can read.
- [TLS certificate](https://tidbit.legios.com.ar/tls-certificate/): The ID card a website shows your browser to prove it is who it claims to be.
- [DNS](https://tidbit.legios.com.ar/dns/): The internet's phone book: it turns names like wikipedia.org into IP addresses.