- Computers are made from loads of switches, all tied together. These control the flow of electricity and are switched on and off electronicly.
- Our program sets the switches to do the job we need doing by controlling the flow of the electricity; for example, it might set the switches to light up the part of the screen needed to show the words "Hello World".
- We can write code that turns the switches on and off by using
1s and 0s.
- But this would be crazyhard to get right, so we need some other way to do this.
- We write using languages which are closer to English and the computer changes this into on and offs.
- Programming languages:
- make it easier to write code without mistakes;
- save us learning the binary needed for different computers;
- hide loads of code inside small commands.
- There is no perfect language to learn, even as a beginner, but Scratch allows beginners to focus on the coding without all the problems of getting the language right.
Key words:
- Binary code:
- writing in ones and zeros.
- Run ( or "execute" ):
- to set a program going.
- Compile:
- what a computer does when it turns our code into ons and offs it can work with.
- Computer language:
- a way of talking to a computer. There are lots of languages, each with a right way of writing them. The computer compiles them all to the ons and offs it needs. Different languages are good for different kinds of jobs. Some are easier to learn, some more powerful. Most programmers know several.
- Coding environment ( usually "Intergrated Development Environment" or "IDE" ):
- software for writing and running code, a bit like you'd use
Word for writing a document. Comes with helpful tools for writing code and executing it. Some languages can be written in text editors like "Notepad" but most people use
some kind of IDE.
So, how do we work with languages? What's inside a typical language?
