Basic concepts to know Flashcards
What are two types of Command Line Interface?
*UNIX
*Windows
What does compile code mean?
Turning code into zeroes and ones, aka Machine Language
What is block level scope?
A block scope is the area within “if, else, switch” conditions or “for and while” loops. Generally speaking, whenever you see {curly brackets}, it is a block
What is ES6?
The 2015 version of JavaScript.
*ECMAScript was created to standardize JavaScript
*ES6 is the 6th version of ECMAScript
*published in 2015
*it’s also knows as ECMAScript 2015.
What are the names of variables called?
identifiers
How do you add JavaScript to an HTML page?
*Use the dedicated HTML tag
< script > that wraps around JavaScript code.
*an external JS document that’s referred to in the HEAD section
*The < script > tag can be placed in the <head> section of your HTML or in the <body> section, depending on when you want the JavaScript to load.
What are HTML tags called if they don’t need an ending tag?
Any of these:
*void
*empty
*self-closing elements
Is an object like a variable?
*Yes, an object is like a variable but with multiple values instead of one.
*it usually has properties and methods
*A car is like an object. It has properties (color, brand, etc.) and things it can do called “methods” (stop, start, etc.)
How do you call an object?
*object name- period-property name.
*If you want to call the property FIRSTNAME from the PERSON object, you would type:
person.firstName
What is JSON?
*it’s a data format used to transmit data in web apps
*JavaScript Object Notation
*an alternative to XML
What is AJAX?
*Lets a webpage communicate with the server without reloading the page
*Stands for Asynchronous JavaScript and XML
*the use of the object named XMLHttpRequest to communicate with servers
What is jQuery?
jQuery is a library
What is an MIT Licesnse?
A permissive free software license
What is a Boolean result?
A result that’s either TRUE or FALSE
What is an operand?
The quantity on which an operation is to be done.
The “subject” of an operation
statically typed
*you have to declare the data type explicitly when you declare a variable.
*The language doesn’t figure it out for you.
*This avoids having a variable be treated as the wrong data type later in the code.
*cf. dynamically typed
dynamically typed
*you do NOT have to declare the data type when you declare the variable
*the language will figure out the best data type.
*This can cause unexpected problems later in the code though when one data type gets treated like a different data type.
*cf. statically typed
What’s the difference between a FOR LOOP and a WHILE LOOP?
FOR LOOP: When we know the number of iterations that must occur in a loop execution,
WHILE LOOP: When we do not know how many iterations must occur in a loop, we use a while loop. It runs until proven false.
What is an integer?
A whole number
What is node.js?
It’s a way to run JavaScript outside of a browser
Used in backend development
