The importance of variables in any programming language can’t be emphasised enough. Even if you are a novice, the chances are good that you will have been using variables for quite a while now.

They are the cornerstone of any language and without them we would not be able to accomplish much of anything. However, most of you up until this point have probably only been working with standard variables, variables which can hold single values such as an integer, a single character, or a string of text.

In this tutorial we are going to take a look at a more special type of variable called an array. Arrays can seem quite daunting at first glance but once you get used to working with them you will wonder how you ever managed to program without them.

The reason arrays are special is because they can hold more than one value. Think about this: say you create a variable which contains a line of text like the code below:

Microsoft has now come up with a surface tablet to compete with the Apple iPad. The Surface is the known as the ‘iPad killer’ and ‘Microsoft iPad’. Microsoft has stuck to production of software till date but this is one of its latest hardware devices that is expected to take over the Apple iPad. This is a new challenge posed by Microsoft to Apple.

            The Microsoft Surface saw its official release on 19^th June in the city of Los Angeles. It has made a great first impression and seems to be beginning a new start in the competition between the best tablets in the international market. It has 10.6’’ screen and a magnetic cover that can be used as a keyboard and also as a kickstand in order to place the device upright on tables. There has been a paradigm shift in Microsoft’s policy when it decided to do away with the tile-based Metro theme for its Desktop that is almost a trademark with it.

            There are many features that make the Surface more like a laptop than like a tablet- the most prominent one being the built- in keyboard that will be useful for business customers. As Microsoft Surface employs Windows 8 as an operating system, which is also used in its computers and laptops, it will be a lot easier for customers to switch among their devices.

            The tablet was announced by Microsoft’s CEO, Steve Ballmer, in Los Angeles at a special press conference. It was hailed to be the first of an entirely new family of a number of devices being created and developed by the company. The Surface has a thickness of 9.3mm and weighs 1.5 pounds. It has a kickstand and keyboard for its cover. It is 0.1 mm thinner than the iPad 3, which is the latest iPad from Apple.

The Zen of Python, by Tim Peters has been adopted by many as a model summary manual of python's philosophy.  Though these statements should be considered more as guideline and not mandatory rules, developers worldwide find the poem to be on a solid guiding ground.

Beautiful is better than ugly.
Explicit is better than implicit.
Simple is better than complex.
Complex is better than complicated.
Flat is better than nested.
Sparse is better than dense.
Readability counts.
Special cases aren't special enough to break the rules.
Although practicality beats purity.
Errors should never pass silently.
Unless explicitly silenced.
In the face of ambiguity, refuse the temptation to guess.
There should be one-- and preferably only one --obvious way to do it.
Although that way may not be obvious at first unless you're Dutch.
Now is better than never.
Although never is often better than *right* now.
If the implementation is hard to explain, it's a bad idea.
If the implementation is easy to explain, it may be a good idea.
Namespaces are one honking great idea -- let's do more of those!

I suspect that many of you are familiar with the term "hard coding a value" whereby the age of an individual or their location is written into the condition (or action) of a business rule (in this case) as shown below:

if customer.age > 21 and customer.city == 'denver'

then ...

Such coding practices are perfectly expectable provided that the conditional values, age and city, never change. They become entirely unacceptable if a need for different values could be anticipated. A classic example of where this practice occurred that caused considerable heartache in the IT industry was the Y2K issue where dates were updated using only the last 2 digits of a four digit number because the first 2 digits were hard-coded to 19 i.e. 1998, 1999. All was well provided that the date did not advance to a time beyond the 1900’s since no one could be certain of what would happen when the millennia arrived (2000). A considerably amount of work (albeit boring) and money, approximately $200 billion, went into revising systems by way of software rewrites and computer chip replacements in order to thwart any detrimental outcomes. It is obvious how a simple change or an assumption can have sweeping consequences.

You may wonder what Y2K has to do with Business Rule Management Systems (BRMS). Well, what if we considered rules themselves to be hard-coded. If we were to write 100s of rules in Java, .NET or whatever language that only worked for a given scenario or assumption, would that not constitute hard-coded logic? By hard-coded, we obviously mean compiled. For example, if a credit card company has a variety of bonus campaigns, each with their own unique list of rules that may change within a week’s time, what would be the most effective way of writing software to deal with these responsibilities?