Add Readme with basic information

README.md

@@ -1 +1,78 @@
-This is a list of useful math functions.
+# JS-Math
+
+## Description
+JS-Math is a library of math functions that allows you to perform common math operations on numbers and arrays.
+
+## Installation
+1) First install nodejs https://nodejs.org/
+2) Verfiy nodejs and npm are installed with commands in the terminal, <code>node -v</code> and <code>npm -v</code>
+3) Run the command <code>npm install math</code>
+
+## Usage
+To use JS-Math import the module in your javascript file 
+```javascript
+const jsMath = require('math');
+```
+To run the file, run the command <code>node file_name.js</code>
+
+## Functions
+There are nine basic functions that can be utilized: samesign, copysign, add, sum, mul, prod, factorial, gcd, and lcm.
+
+#### Samesign
+The samesign function takes two numbers as arguments and returns a boolean whether they have the sign same.
+```javascript
+jsMath.samesign(4, 5); //samesign(4, 5) => returns: true
+```
+#### Copysign
+The copy sign function takes two numbers as arguments and returns the first argument with the same sign as the second argument.
+```javascript
+jsMath.copysign(-3, 6); //copysign(-3, 6) => returns: 3
+```
+#### Add
+The add function takes two numbers as arguments and returns their sum.
+```javascript
+jsMath.add(15, 11); //add(15, 11) => returns: 26
+```
+#### Sum
+The sum function takes an array of numbers as an argument and returns their sum.
+```javascript
+jsMath.sum([2,3,4]); //sum([2,3,4]) => returns: 9
+```
+#### Mul
+The mul function takes two numbers as arguments and returns their product.
+```javascript
+jsMath.mul(3,7); //mul(3,7) => returns: 21
+```
+#### Prod
+The prod function takes an array of numbers as an argument and returns the product of the elements in the array.
+```javascript
+jsMath.prod([8,9,23]); //prod([8,9,23]) => returns: 1656
+```
+#### Factorial
+The factorial function takes a number as an argument and returns the [factorial](https://en.wikipedia.org/wiki/Factorial).
+```javascript
+jsMath.factorial(7); //factorial(7) => returns: 5040
+```
+#### GCD
+The gcd function takes two numbers as arguments and returns their [greatest common divisor](https://en.wikipedia.org/wiki/Greatest_common_divisor).
+```javascript
+jsMath.gcd(126, 48); //gcd(126, 48) => returns: 6
+```
+#### LCM
+The lcm function takes two numbers as arguments and returns their [least common mulitiple](https://en.wikipedia.org/wiki/Least_common_multiple).
+```javascript
+jsMath.lcm(24, 36) //lcm(24, 36) => returns: 72
+```
+
+## Coffeescript
+Additionally, there is a coffeescript file that can be compiled to a javascript file named math.js.
+
+To install coffeescript globally run the command <code>npm install -g coffeescript</code>
+
+To verify coffeescript is installed globally run the command <code>coffee -v</code>.
+
+To compile the coffeescript file run the command <code>coffee -c math.coffee</code> in the same directory as the math.coffee file. This will produce a math.js file.
+
+To read more about coffeescript visit https://coffeescript.org/
+
+## License