DNS Caching

Why
DNS Caching is important because it allows us to save a lot of time on DNS lookups

What
DNS Caching is the process of saving the results of DNS queries at the local DNS servers so that we don't need to run the entire query process every time we want a new domain.

Positive Caching
Local DNS servers store the result of DNS queries and it holds it for a time based on a TTL value and these records are deleted after TTL expires

Negative Caching
Remember what doesn't work and do a short circuit when a future DNS query for the same domain happens. This is not as common and is not always implemented