Programming Concepts

Question 1

What is the difference between data and information?

Answer 1

Computers understand data whereas humans understand information. Computers have to convert information into data in order to process it.

Question 2

What is a constant?

Answer 2

A constant is a value that can’t be changed while the program runs

Question 3

What is a variable?

Answer 3

A variable is a value that can be changed by the program as it runs

Question 4

Why is it important that variables have data types?

Answer 4

Because using the correct data type helps to avoid errors. For example, if a program incorrectly stored numbers using the data type ‘string’, and then attempted to carry out mathematical operations on the is data, it would prove impossible because text data cannot be manipulated in this way.

Question 5

What are the advantages of using Boolean?

Answer 5

• Faster entry of data
• Less memory used
• Lower the chances of errors

Question 6

What is a multi-dimensional array?

Answer 6

An array that can store more than one series of data in conjunction

Question 7

What are the three common relational Boolean operators?

Answer 7

AND
OR
NOT

Question 8

What does each operator mean?
A. =
F. >

Answer 8

A. Less than
B. Less than or equal to
C. Equal to
D. Not equal to
E. Greater than or equal to
F. Greater than

Question 9

What is a procedure?

Answer 9

A set of instructions that form a specific task as part of a larger program

Question 10

What is the difference between a procedure and a function?

Answer 10

A procedure simply executes it’s statements and then returns control to the main program whereas a function also receives and sends values between the program and itself

Question 11

Name and describe three built in functions in a language of your choice.

Answer 11

(C++)
Round- this rounds numbers up/down eg, Round(111.5) returns 112

Abs- this will return the number as a positive eg, Abs(-112) will return 112

Sqrt- this will return the square root of the number eg, sqrt(12544) will return 112

Question 12

What is a parameter?

Answer 12

A value that is sent to a procedure or a function

Question 13

What is a return value?

Answer 13

The data which functions send beck to the main program when they have finished their execution

Question 14

Define scope

Answer 14

The range over a program in which a variable, constant, function or procedure can act

Question 15

Give two types of functions with different scope

Answer 15

Public/global- can be called from anywhere in the program

Private/local- can only be called from an individual area of the program

Question 16

What is an algorithm?

Answer 16

A series of steps or instructions that are followed in order to solve a problem

Question 17

What is pseudo code?

Answer 17

Structured English that describes and algorithm, similar to the real code

Question 18

Describe a sequence

Answer 18

When a set of instructions is executed in order

Question 19

Describe a selection

Answer 19

When an option of statements is provided and a condition is used to decide which option was chosen

Question 20

Describe an iteration

Answer 20

When a group of statements are repeated until a condition is met

Question 21

What is a nested construct?

Answer 21

Using one programming construct within another eg, using a selection within and iteration

Question 22

Describe what is meant by top down design

Answer 22

Solving problems by breaking them down into smaller problems.