See also: MathML
Exponential notation is one way to describe large numbers. In hand-written and academic mathematical notation, exponents are noted by raising the exponent above the base number ("superscript"). Originally this could not easily be displayed on computers, so hackers and programmers took to using the caret symbol (^) to mark the seperator between the base number and exponent. In this Wiki the caret usage is maintained, due to limitations of the Wiki software.
In science, exponential numbers are often notated by using the letter "e". An "e" is equal to "times ten to the power of X", so 3.5e7 means "three point five times ten to the power of seven", 3.5 * 10^7, or 35000000.
Living within the limitations of simple text on the internet can be extremely frustrating for mathematicians and scientists. For this reason, the mark-up language MathML was created - it can correctly display mathematical symbols in a cross-platform manner using XML.
Googol is 10^100, which is a very large number indeed. This is why the search engine Google is named thus.
Word, Notation, Prefix, Numeral
...Octillion, Nonillion, Decillion...