txt allows you to specify which pages should not be crawled.
Pages that don't get crawled can still rank for keywords and show up in search results.
txt has been with us for over 14 years, but how many of us knew that in addition to the disallow directive there's a noindex directive that Googlebot obeys? That noindexed pages don't end up in the index but disallowed pages do, and the latter can show up in the search results (albeit with less information since the spiders can't see the page content).
It is by no means mandatory for search engines but generally search engines obey what they are asked not to do.
It contains restrictions for Web Spiders, telling them where they have permission to search.
It is like defining rules for search engine spiders (robots) what to follow and what not to.
It provides you with more functionality than Meta robots tag which is available only partially to control behaviour of search engines.
You can use it to prevent indexing totally, prevent certain areas of your site from being indexed or to issue individual indexing instructions to specific search engines.
txt protocols are simply advisory though.
There is no law requiring websites to have Robot.
txt files, or to use them on their web pages.
It is the most widely used method for controlling the behaviour of automated robots on your site (all major robots, including those of Google, Alta Vista, etc.
It can be used to block access to the whole domain, or any file or directory within.
It is a text file which instructs search engine spiders or crawlers on what to do.
It tells specific web spiders on which specific web pages to index.
Robots are configured to read text.
Too much graphic content could render your pages invisible to the search engine.
Robot Manager uses a simple user interface that makes creating your robots.
txt file a breeze.
They can come in very handy beyond the search engines.
It is possible to use them to protect your site from malevolent web crawlers, which is useful to say the least.
Robots and spiders aren't bad.
They are generally good.
It is a simple text file which contains some keywords and file specifications.
Each line of the file is either blank or consists of a single keyword and its related information.
Robots can choose to ignore your instructions.
Robots are often used by search engines to categorize and archive web sites, or by webmasters to proofread source code.
The standard is unrelated to, but can be used in conjunction with, Sitemaps, a robot inclusion standard for websites.
It gives spiders (aka, robots) the direction they need to find your most important pages.
This file ensures a spider's time on your site will be spent efficiently and not be wasted indexing pages you don't want them to index.
txt is a file that by convention placed in the main folder of a web site which provides some information to the search engines (the robots) who visit.
Good manners on the part of the search companies dictate that any robots they employ should be "well-behaved", which is to say they obey the limits in robots.
txt, do not overload the site with too many simultaneous queries, and so forth.