---
title: Panther - Full stack Bootcamp - S8 Basic programming
tags: Panther, LearnWorld, Fullstack, JS
---

# Intro to Programming

### Vocabulary

There are a few basic concepts you need to remember. They act like building blocks. To build a tall tower, you start first by putting block on top of block. Here are some of the essential programming building blocks:

- **Variables** to store data (aka state) during your program’s execution
- **Declare**: Creating a new variable (distinct from assignment)
- **Operators**: Symbols that are used to assign, compare, and perform operations
- **Assignment**: Assigning a value to a variable
- **Data Type**: A kind of data, defined by the values it can hold and the operations that can be done on it
- **Statement**: A single piece of code that accomplishes one task or action
- **Expression**: A statement that produces a value
- **Conditionals**: like if statements to make decisions
- **Loops** to repeat tasks until a condition stops being true
- **Functions** to organize your code into logical and reusable chunk

## Variables

A variable is a place to store values. When we write scripts (a set of instructions for a computer to follow), we need to temporarily store small pieces of data. We store that data in variables. “Variable” is a good name for this concept because it indicates the stored data can change (or vary) each time a script is run.

var amount = 9;
amount = amount * 2;
console.log(amount); // 18

// Convert `amount` to a string
amount = "$" + amount;
console.log(amount); // "$18"

## Operators

**Variable Assignment**

a = b * 2;

- `a` and `b` are called **variables**. Variables hold values to be used by the program.
- `=` and `*` are assignment and mathematic **operators**.
- The statement `a = b * 2;` tells the computer to get the value stored in variable `b`, multiply that value by 2, then store the result back to the variable `a`.

**Math**: `+` (Addition), `-` (Subtraction), `*` (Multiplication), `/` (Division), `**` (Exponentiation), `%` (Modulus or Remainder), `++` (Increment), `--` (Decrement)

**Compound assignment**: `+=`, `-=`, `*=`, `/=`. For example `a += 2` is the same as `a = a + 2`

**Equality**: `==` (loose-equals), `===` (strict-equals), `!=` (loose not-equals), `!==` (strict not-equals)

**Comparison**: `<` (less than), `>` (greater than), `<=` (less than or loose-equals), `>=` (greater than or loose-equals)

**Logical**: `&&` (and), `||` (or)

## Statements & Expressions

- **Statement**: A script is a series of instructions that a computer can follow one-by-one. Each _individual instruction_ is known as a statement. Each statement in JavaScript is followed by a semicolon.

var a = 1;
var b = a + 2;
b = b + 3;
console.log(b);

- **Expressions**: An expression is a statement that results in a single value. Expressions can use operators to create this single value. Here are some example expressions:

This expression results in "apple": `"ap" + "ple"`

This expression results in 5: `2 + 3`

## Conditionals

Sometimes we want to perform an action based on some kind of condition. In English, we can say “If this thing is true, then do that.” In JavaScript, conditionals are written very similarly and allow us to take a certain path in our program.

Let’s now look at the basic structure of a conditional:

if (expression) {
  statements;
} else if (expression) {
  statements;
} else {
  statements;
}

var today = new Date().getDay();

if (today === 6) {
  console.log("Today is Saturday");
} else if (today === 0) {
  console.log("Today is Sunday");
} else {
  console.log("Looking forward to the Weekend");
}

## Loops

Repeating a set of actions until a certain conditions fails is the job of programming loops.

**`for` loop**

Sometimes you are looping for the intended purpose of counting a certain set of numbers, like from 0 to 9 (10 numbers). You can do that by setting a loop iteration variable like `i` at value 0 and incrementing it by 1 each iteration.

for (var i = 0; i <= 9; i = i + 1) {
  console.log(i);
}
// 0 1 2 3 4 5 6 7 8 9

**`while` loop**

while (numOfCustomers > 0) {
  console.log("How may I help you?");

  // help the customer...

  numOfCustomers = numOfCustomers - 1;
}

## Functions

A function is generally a named section of code that can be “called” by name, and the code inside it will be run each time.

function toCelsius(fahrenheit) {
  return (5 / 9) * (fahrenheit - 32);
}

Functions can be used the same way as you use variables, in all types of formulas, assignments, and calculations. For example, instead of using a variable to store the return value of a function:

var x = toCelsius(77);
// String concatenation
var text = "The temperature is " + x + " Celsius";
// Template literal
// var text = `The temperature is ${x} Celsius`;

You can use the function directly, as a variable value:

var text = "The temperature is " + toCelsius(77) + " Celsius";
// Template literal
// var text = `The temperature is ${toCelsius(77)} Celsius`;

### Videos 📹

- [A day in the life of a software engineer](https://www.youtube.com/watch?v=rqX8PFcOpxA)
- [Conditionals in JavaScript](https://www.youtube.com/watch?v=Gy87ZS5sb1w)