Data Types and Structures

Data Types and Structures

1. Introduction

   • Programs need to be able to store data such as texts, whole numbers, decimal numbers, etc
   • Data types such as integers and strings are used to store these peices of text, numbers, etc
   • Each data type is stored in the computer's main memory
   • Data types also restrict the actions that can be carried out on them. This helps reduce human mistakes such as trying to multiply two letters together.

2. Strings

   • Strings are used to store text and sequences of characters
   • Eg "Hamster", "Rasperry Fudge Cakes"

3. Integer

   • Integers are used to store positive and negative whole numbers, as well as the number zero
   • Eg 42, 0, -100, 64

4. Real

   • Real data tyoes are used to store positive and negative decimal numbers or fractions.
   • Eg 0.5, 1.236, -5.6

5. Boolean Variables

   • Booleans are used to store only two values: True or False
   • Eg True, or False

6. One Dimensional (1-D) Arrays

   • Many programs requie data to be stored and manipulated not as a single itme but as a list of related data entries.
   • An array is used to store a collection of data where the data is all the same data type
   • Each Element in the array is identified by using an array name and an index number which corresponds to the datas location in the array
   • When an array is created it's length is declared