We all live with computers鈥 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.
The web is full of amazing information. But with literally billions of web pages out there, finding what you need can be鈥 difficult.
Search engines are programs that search the internet for us. But you have to know how to tell it what to look for!
Ada:
Yes. Yes - didn鈥檛 think I鈥檇 ever find that鈥
Voice over:
Let鈥檚 say you鈥檙e in need of some new tops to wear.
Ada:
Oh no!
Voice over:
How can you get a search engine to help you find a new one? You have to tell it what to look for by giving it a keyword. And off it goes鈥
Searching billions of pages for items that match your keyword. But with so much out there a search engine is bound to come back with results that are completely unsuitable 鈥 so you need to know how to refine your search.
To do that you can use what we call Boolean Operator.
Ada:
This is huge 鈥 you could fit two of me in here.
Voice over:
That sounds complicated but it鈥檚 not. Let鈥檚 start with AND. If you have AND between keywords then the search engine will look for pages that match all the keywords that you write.
In fact when you put two or more keywords into a search engine they normally assume that you鈥檝e put AND between them so you鈥檙e probably using AND without realising. It鈥檚 a powerful way to narrow down search results. But it can still include unsuitable results.
Ada:
[Laughs]鈥 Not really everyday wear鈥 but at least it鈥檚 the right size.
Voice over:
Now sometimes you also need to tell the search engine what you don鈥檛 want! So another useful Boolean operator is NOT.
Ada:
Nice but let鈥檚 try something else鈥n a different colour.
Voice over:
But what if you are interested in more than one thing? That鈥檚 where the third Boolean operator comes in - 鈥淥R鈥. Now the search engine will search for any pages that contain either one of your key words.
Ada:
Yay!
Voice over:
Search engines are only as good as the keywords you give them.
Ada:
鈥淲hich one do you prefer?鈥
Voice over:
And they鈥檙e not so good at helping you choose.
Search Engines - good outcomes, need good inputs.
Video summary
The term 'Search Engine' is explained through everyday activities/events.
Computer Head is trying to find a single item in a pile of hay and is doing this by going through all the individual strands of hay.
His friend, Ada, suggests that a search engine would be the best way to search through lots of items to find the item for which he is looking.
She then teaches her friend about Boolean Operators and shows how they help to make searches effective.
This clip is from the series How to Think Like a Computer.
Teacher Notes
This clip could be used to discuss AND, OR, NOT in relation to Logic Gates and Circuits, then relate to programming.
You could use it to discuss Truth tables, conditional operators and George Boole and his connection with Boolean operators.
You could also 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 and KS4 in England, Wales and Northern Ireland and National 4 and 5 in Scotland.
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.
Bias & Reliability. video
A teenage programmer (Ada) asks her computer friend an everyday question to test any bias from the search results offered.
