What is the difference between a checkbox and a radio button?

Checkboxes may be switched independently of each other, while radio buttons are part of a group where only one may be active at a time.

Mutual exclusion

Suppose you open a new application and see something like this:



Try clicking on these radio buttons. You should find that this “application” can walk, and it can chew gum, but not both at the same time.

Independence

What if you later upgrade to version 2.0 of the same application, and see this:

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Why do so many web pages about a topic have exactly the same text?

Because they’re content scrapers.

Plagiarism 1.0 — handwriting

Have you ever seen someone in school write an essay by copying out an encyclopaedia article by hand?  It’s unethical and very tedious.

Plagiarism 2.0 — copy and paste

Computers are good at automating tedious tasks.  Find a web page on the topic, copy it, paste it, print it, and hand it in.  This will free up plenty of time for practising your best “innocent” expression in front of a mirror.  You will need it when your teacher runs a web search using phrases from your essay ((How to cheat good, Alex Halavais, 2006)) and finds the exact site you stole it from.

Plagiarism 3.0 — more copy and paste

If your innocent expression is good enough, you can pass high school — or even University — without learning any skill other than copying and pasting.  What can you do with that skill?

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