Data has always been important to business. While it wasn't long ago that businesses kept minimal information on people who bought their products, nowadays companies keep vast amounts of data. In the late 20th century, marketers began to take demographics seriously. It was hard to keep track of so much information without the help of computers.

Only large companies in the '60s and '70s could afford the research necessary to deliver real marketing insight. The marketers of yesteryear relied upon focus groups and expensive experiments to gauge consumer behavior in a controlled environment. Today even the smallest of companies can have access to a rich array of real-world data about their consumers' behavior and their consumers. The amount of data that is stored today dwarfs the data of only a few years ago by several orders of magnitude.

So what kind of information are businesses storing for marketing purposes? Some examples include:

- Demographic information — age, gender, ethnicity, education, occupation and various other individual characteristics.

Every programming language has a mechanism to allow the programmer to create variables which hold custom data entered in by either the coder themselves or by the user of the application.

Regardless of whether you’re new to programming or not, you will have used variables and you should understand that in javascript they can hold any value such as a number or a string of text.

There is also another type of variable called an Array. Now, depending on who you talk to, some will say an array is actually an object, while others say it is a variable. Neither one is wrong but for the sake of simplicity we’ll refer to it as a variable.

Now, arrays are special because they can hold multiple values as opposed to standard variables which can only hold a single value at one time. If you can, try and imagine that your computer’s memory is made up of thousands of little boxes, and each of those boxes has an address which javascript will use to retrieve the array values when needed.

Checking to see if a directory exists and then creating it if it is not present requires a few lines of code.  Isn't Python great.   Begin by importing the os module and use the exists and makedirs functions.

import os

if os.path.exists(somedirectory):
   os.makedirs(somedirectory)

Jeff Nelson, a former Googler and inventor of Chromebook says on Quora, “One habit I've clung to is writing small prototypes when I'm trying to learn new concepts.
For example, I'll sit down with a book or a web page, and over the course of a few hours, write 30 or 40 programs all of them only a few dozen lines long.  Each program intended to demonstrate some simple concept. This prototyping makes it very easy to try out many concepts in a short period of time.”

Miguel Paraz, Software Engineering Student habit is to “keep a log in a text file or document on my work computer. Before trying to solve a problem, I write it down first. And then I describe the details as they happen.”