2.1.1 Thinking Abstractly

Question 1

What is representational abstraction?

Answer 1

A technique in which excessive details are removed to arrive at a representation of a problem that consists of only the key features.

Question 2

Which form of abstraction involves grouping together similarities within a problem to identify what kind of problem it is?

Answer 2

Abstraction by generalisation

Question 3

What is meant by data abstraction?

Answer 3

A form of abstraction in which details about how data is being stored are hidden.

Question 4

What kind of problems make use of multiple levels of abstraction?

Answer 4

Large, complex problems.

Question 5

How does abstraction allow non-experts to make use of a system?

Answer 5

Hides complex and irrelevant information in abstract models.

Question 6

State two advantages of using abstraction in software development.

Answer 6

Two from:

• Easier for programmers to focus on core elements.
• Reduces the time needed to be spent on the project.
• Prevents program from getting unnecessarily large.

Question 7

Give two applications of layers of abstraction.

Answer 7

• Networking (TCP/IP layer)

- Programming languages

Question 8

State two advantages of using abstraction in programming languages.

Answer 8

• Easier to remember syntax in high-level languages as it is closer to natural language.
• Coding becomes accessible to beginners.

Question 9

How does object-oriented programming use abstraction?

Answer 9

Objects are an abstraction for real-world entities.
Attributes are an abstraction for the characteristics of an object.
Methods are an abstraction for the actions a real-world object is able to perform.

Question 10

What is the difference between abstraction and reality?

Answer 10

Abstraction is a simplified representation of reality