HTML (Hyper Text Markup Language) and CSS ( Cascading Style Sheets) each provide different elements to Web pages. HTML provides the information, data, or story. While CSS provides that design, creativity and flow of the page. Imagen you write a story, a novel. The novel only has the same size, thickness and font text, nothing really stands out. Just lines of text. Here comes HTML - You can change the thickness of the text, add headings, and paragraphs. Now you have a Novel. BUT WAIT! Your story needs something, it missing something? You want to make a Graphic novel. Here comes CSS. With CSS you add and change colour, the flow of content and special font style to make you Novel stand out.
All Programming Language uses Loop and flows control to make perform specific requirements when conditions are meant and completed. Let's use the example of driving as there are rules to follow that are simial to programming. Hey, Autonomous driving is a challenge in programming and the next big thing.
The Document Object Model (DOM) is a programming interface with for HTML documents. The DOM represents the document as nodes and objects. That way, programming languages can connect to the page. A tree diagram can be used to represent the layout of the DOM, See image below.
The DOM is a hierarchical structure, effectively enabling programming languages like JavaScript to changes the content of the Document. JavaScript uses the DOM to manipulate The HTML elements. JavaScript gets hold of specific elements on a page to change them, by adding, moving, removing and changing the style properties of the elements.
Two important features of JavaScript are Object and Array, both are data sets. However, arrays and objects store their data differently. Array's can store data like Integers, strings, and even another array. Data stored in an array is ordered in a specific way. Data items are stored to an index number starting from zero, as computers start counting from 0 up. Once data is stored in the array, you can call a specific data up using the value it is assigned to.
Objects are used to store collections of data. Each data value is stored against a specific key, The keys are names for the specific bit of data in a Objects collection. Each data bit can accessed by calling up the Object and it's key e.g. objectName.keyName
A function is a sequence of code that is written once and can be called upon in a program to do a task or calculation multiple time for separate occasions. If you need to calculate a result of different variables for each set, you don't have to rewrite the formula for the calculation each time. You just write the formula once in the function and then input the variables into the function each time and it returns the result for that set.
