All about computing
to help me with my test
bubble sort algorithms
Algorithms are sets of step-by-step instructions for the computer to follow. They are at the heart of all computer programs.
most simple way to use.
- inputs - ingredients and quantities
- the process - recipe or method
- output - what the finished sandwich will be like
- STEPS!
- Look at the first number in the list.
- Compare the current number with the next number.
- Is the next number smaller than the current number? If so, swap the two numbers around. If not, do not swap.
- Move to the next number along in the list and make this the current number.
- Repeat from step 2 until the last number in the list has been reached.
- If any numbers were swapped, repeat again from step 1.
- If the end of the list is reached without any swaps being made, then the list is ordered and the algorithm can stop.
Most programs are developed using programming languages. Psueducode is not a programming language, it is a way of describing a set of instructions.
There arent a lot of known notations for psuecode but a are a few.
- INPUT – indicates a user will be inputting something
- OUTPUT – indicates that an output will appear on the screen
- WHILE – a loop (iteration that has a condition at the beginning)
- FOR – a counting loop (iteration)
- REPEAT – UNTIL – a loop (iteration) that has a condition at the end
- IF – THEN – ELSE – a decision (selection) in which a choice is made
- any instructions that occur inside a selection or iteration are usually indented
Pseudocode can be used to plan out programs.
Flowcharts
A simple flowchart is just a diagram that represents a set of instructions. Flowcharts use symbols for instructions, the symbols constructs the flowchart and also shows step by step solutions to problems.
Common flowchart symbols
Using flowcharts
Flowcharts can be used to plan out programs. Planning a program that asks people what the best subject they take is, would look like this as a flowchart:
How Google Search works
Which is why I think it is important to know how google search works.
So firstly in my own words--
----Firstly you need to know when you search something up in google you're searching google's index.
----Next in order to search through google index a software called spiders is used, the spiders use its so many arms (not literally) to follow many links on webpages and on that web page they follow other links on it. Finally a huge chunk of information is gathered.
---- Now the question is " is that information reliable? is the webpage what I'm looking for?" well now you've asked questions, in this process google search does the same.
Google search makes sure your web page has the right information needed by asking questions too!
For example - How many times does this keyword appear on this webpage?
- Is this keyword in the title?
- Is this keyword in the URL link?
- Does this webpage have synonyms of the keyword?
More than 200 hundred of them which is why the software spiders are good, they are super fast and deliver your webpage within seconds!
If you are still finding it difficult to understand.. if you're the age between
seven- ten
You can watch the video below which explains how google search works in an animation video.
If you're in the age of eleven to an adult
There will be a video explaining how google search works down below. (the second video)
aNd ThAts tHe End of ThIs TopIc! :)
Bಠಠlean Search
Boolean Searches are really useful! and its important to know the meaning of it and the function.
- AND
- OR
- NOT
- 4. '''' quotation marks.
Are all known as boolean operators.
Boolean search operators help to widen or focus more on what you want to search.
for example-- Cake AND pie
That instantly changes what your searching, web servers can narrow down your search to cake AND pie instead of just cake pie.
It is completely different if you search cake OR pie which means either cake or pie so it'll search both keywords which narrows down your search and it finds what you need quicker.
You can do the same with Cake NOT pie which definitely changes your search.
Lastly quotation marks are the best to use because it narrows your search and it is very specific.
cool fact--- the word boolean comes from George Boole who invented the system.
Quote by George Boole below.
End of topic! :)
Internet communication
The internet allow us to communicate without actually having to be with the person, we can find information in matter of seconds, all this is possible with computers and networks.
Whatever device is connected to the internet is called a global device, the internet is a global network and all the billions of devices connected to the internet can all communicate.
How the internet originated
Agencies were formed in the 1950's by the Unites States Defence Department, like the "advanced Research Projects Agency (ARPA, now known as DARPA) this group was formed because they wanted to develop technology.
The groups were based at universities around the group ARPA scientists could communicate or share information in order for their research. They came up with a solution the ARPA created a network of computers, which they called ARPANET. The other people and groups realized how useful it was and created their own networks, though when they did this there networks couldn't communicate with the other network easily. Then another solution was formed, in the 1970's a protocol was formed, it was called TCP/IP this method allowed the separate networks to communicate with each-other!
When the individual networks connected wide are network (WAN) was created and now it is known as the internet.
Since the internet is so well known this century using it, at the ARPANET consisted 4 computers only!! but now billion of computers are connected to the internet.
When we use sites it is said that we are online, being on those sites below makes you online when you go on them.
- communication via email and VoIp
- sharing of information such as text, images, sounds and videos
- storage of information
- streaming television programmes, films, videos, sounds and music
- playing online games
- shopping
- social networking
- banking
There are loads of social sites!!!
- The internet is known as a global network with like linked computers.
- world wide web can be accessed through websites.
- websites consists webpages where you get information from.
- to access websites you use a web browser. web browsers is a program which displays information on a website, every website has an address like a house address.
- website address is known as its URL.
- A website can be linked by visiting a URL, you can type its URL into the web browser.
- Each URL has http which tells the computer to use hyper text transfer protocol to communicate with the website.
- For us to view the browser has to connect to the internet then finds the website at its address and downloads the information on the site for us to view onto our computers.
- webpages and websites are joined together using hyperlinks, when you click on a hyperlink it takes us to another page or site.
- A global network of computers is called webservers.
- A web server hold websites for other computers linked to the internet to access.
- Holding a website is known as 'hosting'.
- A web server can host one or a lot of websites and webpages.
- When you send information to a we server it is known as uploading.
- When you receiver information from the web server it is known as downloading.
- A web server needs to communicate with loads of computers at the same time not like when you make a telephone call.
- Data packets are formed when a web server is broken up, which takes place when the information is downloaded or uploaded.
- Each communication lasts only miliseconds, the web server can communicate with loads of computers at the exact same time, like having loads of conversations but only saying one word in return.
HTml...
Pages on the internet are created using a language which is called Hypertext Markup Language. It describes
- what information appears on a webpage
- how it appears on the page (formatting)
- any links to other pages or sites
HTMl can be written in a simple text editor like a notepad or a specialist software. IF the document is saved with the file extension, the html can be opened and viewed as a webpage from a browser.
This example HTML code displays a message on a webpage:
<html> <body> <h1>Hello world</h1> <p>This is my first webpage</p> </body> </html>
The code uses tags to describe the appearance of the information:
- <html> states that the document is a HTML document
- <body> states that the information appears in the body of the page
- <h1> states that the following text appears as a prominent heading
- <p> states that this is the beginning of a new paragraph
USING EMAIL
Email stands for short electronic mail. the advantages and disadvantages to email are---
Aside from speed, email has several other advantages:
- It costs virtually nothing to send an email, whereas you need to buy stamps to post a letter.
- The same email can be sent to many people at the same time.
- Assets, such as text, videos or sound clips, can be attached to email.
- A record is kept of each sent email, so it is possible to refer back to check what was sent.
- Emails can be sent at any time or day of the year. Post is not usually delivered on Sundays or bank holidays.
- Emails can be sent and received on various internet connected devices, eg PCs, laptops, games consoles, tablets or smartphones.
- Emails can be automatically forwarded on to another address.
Using email has its disadvantages too:
- The recipient can only receive the email if they are connected to the internet.
- Emails can sometimes have viruses in the form of attachments!
- Because emails can be delivered to internet-connected digital devices anywhere, they can be hard to get away from.
Email is a hugely popular form of communication for businesses and individuals alike. Nearly 200 billion emails are sent each day.
And for VoIP it's is really useful and good because people can communicate face to face however people used it for business and academics at first, but now it is used socially by people.
VoIP stands for voice over Internet Protocol.
If people use it they need a webcam, monitor , speakers and microphone.
Advantages and disadvantages are--
- Seeing as well as hearing the other person.
- Showing others what is going on around us.
- Reducing time to travel to see and speak with someone. This has even greater benefits if the other person is on the other side of the world.
- Saving money, in travel costs.
- The ability to video conference several people in different locations, at the same time.
Using video conferencing also has its disadvantages:
- Everyone who wants to video conference must have suitable hardware and software.
- Video conferencing from smartphones can be expensive because of the high data usage.
- You can struggle if you have poor internet.
How to trace websites.
There are two types of ways to trace a website there is either a proxy trace or a host trace.
A host trace will trace your website through the main important IP- addresses until it gets to the one you searched for which is why it takes a shorter time, under 30 seconds.
Lastly a proxy trace takes about 60 seconds because it has to find out all the IP addresses in order until it reaches the end of the result and it goes from countries to countries.