A more thorough explanation:

A denial-of-service attack is a type of cyber attack that is designed to make a computer, website, network, server, or database inaccessible. This is usually done by overwhelming the target with activity or by forcing it to malfunction. It is also known as a "nuking" attack and is abbreviated as DoS attack.

Another type of denial-of-service attack is a distributed denial-of-service attack (DDoS attack). This is carried out by distributing a virus that infects many computers and causes them to try to access the target computer at the same time. This can cause the target to become overwhelmed and unable to function properly.

For example, imagine a website that sells concert tickets. A hacker could launch a DoS attack against the website, causing it to become overwhelmed with traffic and unable to process orders. This would prevent people from buying tickets and could cause the website to lose money.

In another example, a group of hackers could launch a DDoS attack against a government website in order to protest a new law. By infecting many computers with a virus, they could cause the website to become inaccessible to the public, making it difficult for people to access important information.