How does adding an ip/web address to the hosts file block traffic?

Your operating system will first look at the hosts file before attempting to look for name resolution elsewhere. The hosts file is much quicker than querying the network so if the OS can find the answer there then it is one less query to do elsewhere.

The hosts file doesn't "block" traffic, it gives an answer to a lookup to provide a quicker answer than having to send the request elsewhere that may take much longer to provide the desired answer.

Similarly how an SSHD will store the most frequently accessed data on the SSD (as it is much quicker to access) than on the mechanical portion of the SSHD (which is much slower to access).

Recent Questions...