A string is a data type used in programming.  It can contain a variety of different information.  A string can be a word, a sentence, words and numbers, symbols, or any combination of these things. Read more about strings.

SSI stands for server side include. This means that something is included in the file on the server before it is sent to the user.  This is used a lot in PHP when we have different parts of our page or program held in different files.  [read more]

A Floating Point Number is a way to represent a precise number on a computer system. The "floating point" refers to the decimal point. Other than this it is very similar to scientific notation. Using this sort of notation when storing numbers in the computer lets you work with more accuracy and lose less digits than you might have otherwise lost.

Boolean logic is usually taught along side of computer programming because it helps people understand how computers think.  A computer can only test for true or false.  Either a condition that you give it is met or it is not.  This article explains how boolean logic works, and how that relates to programming.