Javascript
Overview:
2 sessions
Subjects:
- JS in webpages
- JS data types & variables
- loops
- control structure
- functions
What is JavaScript?
JavaScript is a scripting or programming language that allows you to implement complex things on web pages — every time a web page does more than just sit there and display static information for you to look at — displaying timely content updates, interactive maps, animated 2D/3D graphics, scrolling video jukeboxes, etc. — you can bet that JavaScript is probably involved.[1] </blockque>
Variables
https://codepen.io/PublicationStation/pen/wmpRyX
A variable is a container for some value. Like a number to be used in a sum, or a text string.
Most importantly: variables' values can change. They aren't the values themselves, but containers for values, like little boxes that you can store things in.
https://mdn.mozillademos.org/files/13506/boxes.png [2]
In order to use variables, we need to:
- declare the variables
- values can be attached to them
https://codepen.io/PublicationStation/pen/ZxvwpW
Data types
JS features a few data types, or in other words different types of content, which can be used as values of a variable. These include:
- strings: pieces of text, always wrapped in single or double quotation marks
var name = "I am Pluto";- numbers (both integers and float point numbers)
var discovered = 1930;- booleans: true or false values (outside quotation mais)
var planet = false; var dwarf=true;- Arrays (or lists): a container of multiple values enclosed in square brackets and separated by commas
var planets=["Pluto", "Neptune", "Uranus", "Saturn"]
- the values of arrays can be accessed by their location within the array var
p=planets[0]; var s=planets[3]- Object: HOW TO BEST DESCRIBE IT
var saturn = {"moons": ["Pan", "Daphnis", " Atlas", "Prometheus", "Pandora"], "Volume":"95.159 Earths"}
{{#widget:Iframe |url=https://codepen.io/PublicationStation/pen/ZxvwpW/ }}
See the Pen <a href="https://codepen.io/PublicationStation/pen/ZxvwpW/">JS:variables2</a> by Publication Station (<a href="https://codepen.io/PublicationStation">@PublicationStation</a>) on <a href="https://codepen.io">CodePen</a>.
<script async src="https://static.codepen.io/assets/embed/ei.js"></script>
References
- ↑ "What is JavaScript?" MDN Web Docs, 28 Mar. 2018, https://developer.mozilla.org/en-US/docs/Learn/JavaScript/First_steps/What_is_JavaScript.
- ↑ "Storing the information you need — Variables." MDN Web Docs, 28 Mar. 2018, developer.mozilla.org/en-US/docs/Learn/JavaScript/First_steps/Variables.
