How A records work in a browser
In simplified terms, the process looks like this. When you type a domain name into your browser, for example example.com, it sends a resolve request to a DNS server; the server looks up the corresponding A record (or AAAA record) and retrieves the IP address, for example 192.168.0.1.
The browser then builds a GET request (or POST), setting this IP address as the destination in order to fetch the site's content. The process is described in more detail in the article How a browser works
What else A records are used for
Despite the simplicity of their function, the uses of this record type are very diverse:
- Creating subdomains — A records can be used to set up subdomains (for example, blog.example.com), pointing them to different IP addresses, such as separate servers to split the load.
- Geolocation-based load distribution — with A records you can direct users to servers located closer to them, improving load speed and the overall quality of access.
- Dynamic DNS — A records are exactly what make the Dynamic DNS service work, providing the host's current IP address on request.
A records play a crucial role in ensuring the availability and reliability of websites and other internet services, essentially being synonymous with the word DNS.
