Step 1: Create a folder crud-api
$ mkdir crus-api

Step 2: Create package.json
$ npm init -y

Step 3: Install 
a. express: A web framework for Node.js that simplifies the routing and handelling HTTP requests.  
b: body-parser:  Middle ware for parsing incoming request bodies (POST / PUT)
c. fs module : A built-in module to intract with the file system

$ npm install express body-parser fs

Step 4: Set up the server - Create a file name "server.js" in root directory 

Task:

1. Restrict Duplicate data while add
2. add new item in object as Company and Mobile Number
3. always save name, company like first letter of words should be capital