What does "User-agent: * Disallow: /" mean? [closed]

Question

On a /robots.txt page, what does this mean?

User-agent: * 
Disallow: / 

Does this mean that you cannot search and get results of this website on a search engine? For example does it block Google?

Answer 1

It blocks (good) bots (e.g, Googlebot) from indexing any page.

From this page:

The "User-agent: *" means this section applies to all robots. The "Disallow: /" tells the robot that it should not visit any pages on the site.

There are two important considerations when using /robots.txt:

• robots can ignore your /robots.txt. Especially malware robots that scan the web for security vulnerabilities, and email address harvesters used by spammers will pay no attention.
• the /robots.txt file is a publicly available file. Anyone can see what sections of your server you don't want robots to use.

Answer 2

See the robots.txt specification.

User-agent: * matches every bot that supports robots.txt (and hasn’t a more specific record in the same file, e.g. User-agent: BotWithAName).

Disallow: / forbids those bots to crawl anything on your host.

Note that not all bots support and respect a robots.txt file.