We all live with computers but getting the most out of them鈥 getting them to do what you need鈥 can be kind of difficult.
But if you can understand how they process things, a computer can be the most useful housemate you鈥檒l ever have.
Some tasks seem very simple 鈥 like following a recipe - but even simple things can be complicated for computers. They don鈥檛 know which details are important and which aren鈥檛. While we know the colour of an egg doesn鈥檛 matter. Computers are not that smart.
So you have work out for them what things are relevant and what can be ignored.
We call that Abstraction. But it really just means telling the computer to focus on the essentials鈥
Let鈥檚 say you wanted to start a dance troupe 鈥 and maybe you held the audition鈥t home. How would you explain to a computer who to let in and who to turn away?.. To solve this task the computer needs to be told what鈥檚 relevant and what isn鈥檛.
You might tell it to look out for a whole load of different things鈥 So you didn鈥檛 waste your time auditioning the wrong kind of people.
[crowd sighing]
Abstracting is working out which of those details are important.
If we don鈥檛 get it right, our algorithms won鈥檛 work properly.
To put together a dance group, what鈥檚 important is that they are willing to dance and also actually can dance. What isn鈥檛 important is what they鈥檙e wearing or the colour of their hair鈥 That鈥檚 abstraction for you.
Ada:
Okay everybody, form the top. And one and two and four鈥 And鈥 Dog?
[Dog sighing]
All we need to do now is add 鈥楤EING HUMAN鈥 to the list!
Abstraction - identifying what鈥檚 important.
Video summary
A teenage programmer finds out how to use abstraction in programming.
She gives instructions to her "computer" - a human figure with a monitor for a head.
She asks him to let people in for a dance audition, only choosing those who can dance and want to dance.
Because she doesn't specify in her code that the dancers have to be human, an enthusiastic little dog is among those selected to audition.
Abstraction means telling a computer what information is important and what isn't.
These clips are from the series How to Think Like a Computer.
Teacher Notes
Discuss other situations and abstract the main parts, e.g., look at games (board or computer) and abstract the main parts.
Link to object oriented programming, hiding of data and encapsulation.
Discuss the contributions of women in IT such as Ada Lovelace as the main character is called Ada.
This clip will be relevant for teaching Computer Science at KS3 in England, Wales and Northern Ireland and 3rd Level in Scotland.
Algorithms. video
Why do computer programs use algorithms?
What is decomposition? video
A teenage programmer discovers how decomposition works through trial and error.
Pattern Recognition. video
A teenage programmer is giving her computer instructions on making a sandwich.
