Disk Operating System abbreviated as DOS is a product of Microsoft Corporation released in 1980 and it comes as part-and-parcel with all Microsoft Windows operating systems. To get to DOS prompt and give commands for performing tasks on files and directories, Click Start > Run... and type command or cmd and press ENTER.

Windows is a series of most popular operating systems developed by Microsoft for use on personal computers. First edition of Windows that runs on MS-DOS 5.0 was released in 1985, as a 16-bit OS. Of all the editions of Windows OS released by Microsoft Corporation from 1985 till date, the popular ones include Windows 98, Windows 2000 Professional, Windows XP, Windows Vista and Windows 7. Read more on Evolution of Windows

Coming to differences, here are 5 basic ones that differentiate DOS and Windows:

DOS	Windows
Single user	Multi User
Single tasking	Multi tasking
Not time Sharing	Time sharing
Input device keyboard	Input devices mouse and keyboard (standard)
Character User Interface (CUI)	Graphical User Interface (GUI)

Continue Reading >>5 Basic Differences Between MS-DOS and MS-Windows

Poisson Distribution

Just like Binomial Distribution, Poisson Distribution is also a random variable distribution. We apply Poisson distribution in any one of the following cases:

1. n, the number of times that the experiment is conducted is sufficiently large.


2. Occurrence of success is rare.


3. Occurrence of success is frequent.

In Poisson distribution, values of random variable are the number of successes.

If λ is a parameter then probability of getting k times success is

Now Poisson distribution with parameter λ can be written in tabular form as follow:

Theorems :-

1. Arithmetic Mean of Poisson variable X whose parameter is λ, is λ


2. Variance of a Poisson variable X with parameter λ, is λ

Continue Reading >>What is Poisson Distribution

Phantom Loading

When a energy meter is designed for high current loads, it is uneconomical to arrange such loads for testing purposes as it involves a considerable waste of time and power. To avoid this problem "phantom" or "fictitious" loading is done.

In phantom loading, pressure coil is excited from normal supply voltage and current coil is excited from a separate low voltage supply. The low impedance of current coil circuit makes it possible to circulate the required current even with low supply voltage.

Continue Reading >>What is Phantom Loading

English is a language which is important, useful and helpful for every citizen in today's world.By learning English, we can develop four important skills like:

• Listening
• Speaking
• Reading
• Writing

Knowledge of English is important as we can get to know how to frame sentences, how to use words in dialogues while speaking to others. As every word has a particular context where it fits right, using words in such a manner in English is a art that can only be mastered by practice. And with such command, we can easily communicate with others on any level. Mostly, listening and speaking improves our command on English language. Daily listening to English speakers and trying speaking in English, helps you to know how to use the language, where to use each word and when to use it in a correct manner.

Concentration on learning English communication skills in this new millennium, is a tremendous move towards speaking and writing fluently in English. Also our way of pronunciation of different words will be improved if we learn good communication. We can make conversation, practice dialogues, give presentations if we learn English communication language skills. Communicating with people in English on a daily basis also improves our pitch & voice/tone of our speech; how to speak in a correct form & for correct usage.

Advantages of learning English language communication is an endless list, creating possibilities each day to connect with people worldwide. With command over English language you can get jobs easily and can participate in interviews and discuss with people in a group about any particular important topic or aspect. English communication gains us wisdom and we can also gain lots & lots of knowledge by reading newspapers, story books, essays, online sites and journals and any of the greatest and famous writing written in English by poets, authors or leaders.

Apart from being most important, widely used and useful, English is considered to be one of the easiest languages to learn and speak. With daily practice, you can communicate-well with others and improve your skills, show-off or expose your skills before others to impress and motivate them to come up with their English language communications skills. Hence, English even-though being a foreign language to many is now most commonly used language worldwide especially in British dominion later became Independent republican countries like India and Pakistan. Proud to be an Indian, speaking foreign language, so people around you can't understand.

Continue Reading >>Importance of English Language Communication