Introduction

The search engine syntax

• + A leading plus sign indicates that this word must be present in every piece of information returned.
• - A leading minus sign indicates that this word must not be present in any piece of information returned.
• < > These two operators are used to change a word's contribution to the relevance value that is assigned to a piece of information. The << operator decreases the contribution and the >> operator increases it. See the example below.
• ( ) Parentheses are used to group words into subexpressions.
• ~ A leading tilde acts as a negation operator, causing the word's contribution to the information relevance to be negative. It's useful for marking noise words. A piece of information that contains such a word will be rated lower than others, but will not be excluded altogether, as it would be with the - operator.
• * An asterisk is the truncation operator. Unlike the other operators, it should be appended to the word, not prepended.
• " The phrase, that is enclosed in double quotes ", matches only pieces of information that contain this phrase literally, as it was typed.

Some examples:

• Searching for apple banana find pieces of information that contain at least one of these words.
• Searching for +apple +juice find pieces of information that contain both words.
• Searching for +apple macintosh find pieces of information that contain word "apple", but rank it higher if it also contain "macintosh".
• Searching for +apple -macintosh find pieces of information that contain word "apple" but not "macintosh".
• Searching for +apple +(>pie <strudel) find pieces of information that contain "apple" and "pie", or "apple" and "strudel" (in any order), but rank "apple pie" higher than "apple strudel".
• Searching for apple* find pieces of information that contain "apple", "apples", "applesauce", and "applet".
• Searching for "some words" find pieces of information that contain "some words of wisdom", but not "some noise words".