Unit 4 · Lesson 1
Build the idea
Start with the concept and its key vocabulary.
A data type tells the computer what a value means. 123 is an integer that can be used in calculations. "123" is a string containing three characters. Real values can have decimals, Boolean values have exactly two states, and a character is one symbol. Choose the type from the value's purpose, not just how it looks.
A classification that controls what data can be stored and which operations can be used.
A sequence of characters used for names, text, identifiers and phone numbers.
A whole number with no decimal point.
A numeric value that can include a decimal part.
A value with exactly two possible states: true or false.
A single letter, digit, symbol or space.