Web Spiders, Sometimes Referred to As Web Crawlers

A spider is a software program that travels the Web (hence the name “spider”), locating and indexing websites for search engines. All the major search engines, such as Google and Yahoo!, use spiders to build and update their indexes. A spider is a program that visits Web sites and reads their pages and other information in order to create entries for a search engine index. The major search engines on the Web all have such a program, which is also known as a “crawler” or a “bot.”Spiders are typically programmed to visit sites that have been submitted by their owners as new or updated. There are many thousand different kinds of spiders.

Crawling

Crawling is fast, thanks to multithreading that allows up to 50 simultaneous threads. Crawlers can also be used for automating maintenance tasks on a website, such as checking links or validating HTML code. Also, can be used to gather specific types of information from Web pages, such as harvesting e-mail addresses (usually for spam). Crawling the internet can start from a single point (starting with a popular website containing lots of links, or from an existing, older indexes of websites. The crawler (also known as a web robot or web spider) is a software program that can download web content (mainly web pages but also, in some cases, images, documents and other files) and then follow links within these web pages to download the linked contents.

Visual

Visual Web Spider extracts title, keywords, description, plain text content, HTML content, size and last modified time from the web pages. It allows you to export the extracted data into Microsoft Access database, text file (ASCII), Excel file (CSV), HTML file, mySQL database, directory management system. Visual Web Spider is a website crawler, fully automated, multithreaded web robot. It helps you to populate a database of websites, META data and locate relevant information for research purposes.

Search

Search engines such as Lycos and Alta Vista, have become a commercial success as a result of our desire for information. Search Submit comes in two flavors, Basic and Pro, with the Pro version offering the advantage of providing greater control over the way your listings are presented, helping to raise your click appeal.

Spider technology is necessary because the amount of information being added to the Internet on a daily basis is more than any human team can index. Spider technology is not unusual; it is now used by all the leading search engines. However, the advanced ways in which Google is able to compare the data collected is what has put them on top.



Source by Thulasizwe Kenneth Sukati