AQA GCSE Computer Science with
Complete Solutions
Consists of raw facts and figures without context or meaning. - Ans -Data
What exists when data has been given context or meaning. - Ans -Information
Space for a single piece of data, each variable has a data type. You can change variables
once they have been set. - Ans -Variable
Space for a single piece of data, each constant has a data type. You cannot change
constants once they have been set. - Ans -Constant
A data type, can be either true or false and requires only one bit of storage. - Ans -
Boolean
A data type, a single letter, number, punctuation mark, space etc. - requires one byte. -
Ans -Character
A data type, stores any number of characters, such as a person's name, address and
postcode. - Ans -String
A data type, whole numbers, such as a person's age or how much stock a shop has. -
Ans -Integer
A data type, decimal numbers, such as distances and fractions. - Ans -Real
1
Page
,If you see AND between two Boolean expressions, the whole expression is true only if both
of the smaller expressions are true. For example: age <= 16 AND age >= 5 - Ans -
Boolean Operator - AND
If either of the expressions either side of the OR is true, then the entire expression is true. -
Ans -Boolean Operator - OR
Adding NOT to an expression simply makes it the opposite of what it was before. For
example: NOT (age <= 11). This covers all other ages, 12 and up. - Ans -Boolean
Operator - NOT
>= Greater than or equal to
< Less than
= Equal to
!= Not equal to - Ans -The meaning of the following operators:
>=
<
=
!=
An array is a space in memory reserved for more than one item of the same data type. -
Ans -Array
Table of items and elements, with columns and rows. Data stored in this way can be
considered as if it were in a spreadsheet, where each row and each column stands for
something. - Ans -Two Dimensional Array
2
Page
, Records can combine different data types, and each record would be about one person, or
one building or one book. - Ans -Record
Using data structures instead of lots of individual variables can reduce the amount of code
you need to write in order to solve a problem. Arrays also reduce the likelihood of errors
occurring, as there are fewer places in the code in which errors could exist. - Ans -
Why we use Data Structures
For large programs, different tasks can be assigned to different programmers, with clear
understanding of who is to code what.
Each component can be tested separately as it is coded, which means the complete
program, when all the parts are assembled, will possibly contain fewer errors.
If the program needs updating later, the individual component can be updated, leaving the
rest of the program unchanged. - Ans -When programs are designed, why are they
broken down into smaller tasks and each task is addressed individually?
To solve a problem. - Ans -Why Computer Programs are Written
A step-by-step set of instructions to allow a computer to solve a problem in a finite number
of steps. - Ans -Algorithm
Shows how a program, or a potential program, is broken down into individual processes. -
Ans -Structure Diagrams
A way of showing, within a program, what tasks are to happen in what order. This is done
using shapes and arrows. - Ans -Flow Charts
Used to mark the start and another is used to mark the end of a flowchart. - Ans -
3
Terminator (Flow Chart)
Page
Complete Solutions
Consists of raw facts and figures without context or meaning. - Ans -Data
What exists when data has been given context or meaning. - Ans -Information
Space for a single piece of data, each variable has a data type. You can change variables
once they have been set. - Ans -Variable
Space for a single piece of data, each constant has a data type. You cannot change
constants once they have been set. - Ans -Constant
A data type, can be either true or false and requires only one bit of storage. - Ans -
Boolean
A data type, a single letter, number, punctuation mark, space etc. - requires one byte. -
Ans -Character
A data type, stores any number of characters, such as a person's name, address and
postcode. - Ans -String
A data type, whole numbers, such as a person's age or how much stock a shop has. -
Ans -Integer
A data type, decimal numbers, such as distances and fractions. - Ans -Real
1
Page
,If you see AND between two Boolean expressions, the whole expression is true only if both
of the smaller expressions are true. For example: age <= 16 AND age >= 5 - Ans -
Boolean Operator - AND
If either of the expressions either side of the OR is true, then the entire expression is true. -
Ans -Boolean Operator - OR
Adding NOT to an expression simply makes it the opposite of what it was before. For
example: NOT (age <= 11). This covers all other ages, 12 and up. - Ans -Boolean
Operator - NOT
>= Greater than or equal to
< Less than
= Equal to
!= Not equal to - Ans -The meaning of the following operators:
>=
<
=
!=
An array is a space in memory reserved for more than one item of the same data type. -
Ans -Array
Table of items and elements, with columns and rows. Data stored in this way can be
considered as if it were in a spreadsheet, where each row and each column stands for
something. - Ans -Two Dimensional Array
2
Page
, Records can combine different data types, and each record would be about one person, or
one building or one book. - Ans -Record
Using data structures instead of lots of individual variables can reduce the amount of code
you need to write in order to solve a problem. Arrays also reduce the likelihood of errors
occurring, as there are fewer places in the code in which errors could exist. - Ans -
Why we use Data Structures
For large programs, different tasks can be assigned to different programmers, with clear
understanding of who is to code what.
Each component can be tested separately as it is coded, which means the complete
program, when all the parts are assembled, will possibly contain fewer errors.
If the program needs updating later, the individual component can be updated, leaving the
rest of the program unchanged. - Ans -When programs are designed, why are they
broken down into smaller tasks and each task is addressed individually?
To solve a problem. - Ans -Why Computer Programs are Written
A step-by-step set of instructions to allow a computer to solve a problem in a finite number
of steps. - Ans -Algorithm
Shows how a program, or a potential program, is broken down into individual processes. -
Ans -Structure Diagrams
A way of showing, within a program, what tasks are to happen in what order. This is done
using shapes and arrows. - Ans -Flow Charts
Used to mark the start and another is used to mark the end of a flowchart. - Ans -
3
Terminator (Flow Chart)
Page
