Friday, June 10, 2011

Computer and Data Security

When we work on the computer, we need protection for our saved work and softwares installed on the computer so that some others can not damage or disturb our saved data or our installed softwares
Now computer itself does not know that who is the actual user or who is the authorized person to use the particular data and software. So, we, users have to do some needful steps to ensure the security of our device called “Computer” first of all you should lock the computer room and control the access of other people to use the computer. After that operating systems offer you to control the security by User Id and Passwords so that the only authorized persons could use the data according to given permissions and rights. Furthermore, additional devices are also being used to increase the security level. These additional devices are biometrics; means that devices recognize your voice, your finger prints and even eye retina. After recognizing your identity, these devices allow you to further processing.
So we summarize our discussion in the following words that, when we use computer, we store our data and need protection or security of that stored data and installed softwares so that some other person could not read, edit or delete that data. Computer itself unable to recognize the authorized person so we have to do some steps to ensure our security.
Like to lock the and protect the computer in computer room, use the “USER ID” and “PASSWORDS” to protect and secure the date, use additional biometric devices to control the security Thanks for spending your time and read the post, in our next posts we will further discuss on security, antivirus and data protection

Monday, June 23, 2008

Basic Architecture of Computer

Like a human structure, computer also has a standard structure which called “Computer Architecture”. As, we human beings have different parts of body to perform our daily activities, Computer too has different devices to perform jobs assign to it. The combination of these devices is called computer architecture. The main and the most important part of the computer Architecture is CPU, stands for Central Processing Unit. It controls all the instructions of computer. Or in simple words, we can define CPU as the brain of computer. The CPU has further two parts, one is called “CU” Control Unit and second is called “ALU” Arithmetic logic unit. The function of CU (Control Unit) is to read and decode instructions and execute these instructions one by one. Where as the ALU (Arithmetic Logic Unit) performs the mathematical operations such as addition, multiplications. The combination of these two is called CUP (Central Processing Unit), which we have already discussed works as the brain of human mind.
The second important part of computer Architecture is its main memory. The main memory used to store the programs. CPU takes the data/instructions from main memory and process/execute upon these instructions and then again sends these instructions back to memory for storage or other purposes required by the users. The main memory also has two basic types one is called “Random Access Memory” (RAM), and the second is called “Read Only Memory” (ROM). Main Memory is the long topic to discuss in detail but here in this post only the main function of memory is enough to mention. (How it works, let this topic for another post). Another important part of the computer architecture is the Input/Output devices. As we have discussed about these Input/Output devices in our early posts. Input devices are used to give the instructions to computer and on the other hand output devices are used to present/display the results. Bus interconnection is also very important part of the computer architecture. These bus interconnections are used to link/connect the different devices (parts of computer Architecture) with each other. Or in other words, these bus interconnections used for the transportation of instructions from one device to other.
So, in the end, we can summarize our post that Computer Architecture is the structure of computer, where we discuss the basic and major devices of computer. First of all, we talked about the CUP (Central Processing Unit) there are two main portions/ parts of CPU, first one CU (Control Unit) performs the de-code of instructions and second part of CPU is ALU (Arithmetic Logical Unit) used to perform mathematical operations. Next we talked about the main memory (also has two types RAM and ROM) used to store programs. Input/Output devices are also used to connect the devices with each other. And these but interconnections are the source of transportation for instructions from one device to other.

Sunday, April 6, 2008

Use of computer in the fields of Education and Medical

When we look around our daily life, we find two very major departments; the medical department and the education department. The computer is playing a very vital role in the both of these departments. As for as the medical field is concerned, computer is serving too much in this field, first we check that what are the activities, which performed in a field of Medical. First of all research; the computer helps too much to research about the virus and treatment. With the help of Internet scientists can share their research work and that research work is available in any part of the word. So, this helped too much and now the treatment is possible for such diseases, which were considered incurable in the past.
Secondly, when we talk about the hospital activities, first of all computer is helping in the administrative departments of the hospital. The help of computer in the administrative department is same as it helps in ay factory or office’s administrative department such as to keep the record of employees, prepare the salaries of staff and keep record of that salaries, furthermore, keep the record of daily visits of patients. So, we can easily know the number of daily visits of patients. In this way, records of patient remains save in the hospital’s database. Furthermore, doctors also maintain the history of patients as well as the history of treatment, which the doctor is providing to his patient. There is also some medical equipment, which is controlled by the computers. These computer controlled equipments observe patient second by second and alerts if find any critical situation so, this was the role of computer in the field of medical.
Now, we discuss the role of computer in the field of education. The history of the computer use in the educational field starts from 1970 when the microcomputer invented. There are two major fields in the education department. One is learning and second is teaching. The use of computer is very helpful in both fields. When we talk about the learning skill, the students can learn from computer as they can learn from any teacher. There are softwares available in the market, which conduct tests, drill and testing skills. There are also some softwares available which help the teachers to explain the concepts in better ways. The use of computer makes it very easy and helpful to teach difficult subjects in easy way.
So, in the end of this post, we can summarize our discussion that computer is helping us in the field of medical and education in the field of medical computer used to perform administrative tasks as well as to keep the record of patient’s disease and the treatment provided to him. And computer is also helpful in the field of medical research.
Computer is also very beneficial in the educational fields. These major educational fields are learning and teaching. In leanings, there are computer softwares, which provide drilling and practice exercises and students can check his knowledge by using testing softwars. On the other hand, when we talk about teaching, with the help of computer it is easy for the teachers to explain the concepts in better ways. Furthermore, tutorial sotwars are also available in the market.

Sunday, March 16, 2008

The Use of Computer in our life

In our previous post we talked about the use of computer in industry. We looked that how computer helps us in office or factory environment. Today we will see that how computer is helpful in our other matters. It has become that part of history when the mail delivery took too much time to reach to reach its destination. Now, with the help of computer our message reaches to its destination just within a second. This type of mail is called Electronic Mail or E-Mail; we can send E-Mail in any type of data. Such as text, image, audio and video. If we want to send simply text message, we will just type our message and then send it, but if we want to send other data type file, we will use the attachment facility. We can attach the other file with our mail and that file/files also delivered to the desired E-mail address. So, in short, we can say that the use of computer in the field of mail brought a very positive change and now the mail delivery time has been reduced from days to seconds.
It was also a long process to arrange the meetings. First of all, inform the members about the meeting place and time, then the participants will prepare on their end. They have to travel long distances, some had to travel from one city to another. But the use of computer has made it too much easy to arrange meetings or in other words, we can say that the traditional meetings have been replaced with the videoconferences. All the participants take part from their offices or from their homes. They just need a computer and Internet connection. So, all members can share their ideas and views along with their live videos.
Another major advantage of computer use in our life is it, that it brought a revolutionary change in the field of Banking, this called E-Banking. With the help of E-Banking, our accounts and all other bank related activities remain under our access or observation twenty-four hours. We can check our bank balance with ATM and we can also withdraw amount any time. We can check our balance through computer and Internet and even from our cell phone. So, E-Banking is also due to the use of computer in the field of banking.
The use of computer has also made our sale and purchase very easy. Now, where it is easy for the manufactures to sale their products, it also very useful for the customers to purchase. Now, the customers can purchase anything and anytime from their home. We need just a computer and Internet connection. We will visit to products web site and then we can place our online order.
So, in the end we can summarize our post “ The use of computer in our life” in the following words that the use of computer has totally changed our life. We find computer in almost all the major departments of our life. In our previous post we discussed how computer is helping us in offices and factories. In this post we talked about E-Mail, E-Conference, E-Banking and E-Shopping. E-mail is the replacement of our traditional mail system and now we can send mail along with other file attachments just in seconds, where as in past, it was a long and time taking activity. E-Conference is the replacement of traditional meeting system and now the participants can participate from their offices or even from their homes. And same way E-Banking made it possible that we can use all the banking services from our homes and due to the E-Shopping we can purchase anything anytime from our home and on the other hand, E-Shopping is helpful for manufactures to sale their products.

Saturday, March 1, 2008

The Role Of Computer In Business

Almost two hundred years ago, nobody was familiar with the word of computer and it was unbelievable at that time that one day computer will become the essential part of our daily life.
Today the use of computer has become compulsory in the all fields of our life. Here we will discuss the use of computer in our daily business life. Once there was a time when offices were full of registers and files and factories and offices have large record rooms full of register and manual workings. And it was a hard activity t find about anything. But now, the computer has made it too much easier to manage our data. We manage the records of our employees, all personal information of employees. Furthermore, we store and manage the daily attendance of employees, their “Time-In” and “Time-Out”, in short, we generate our payroll with the help of computer and store all the employees’ personal records and it is too much easier to locate any specific record.
There is also accounting software available in the market, which, help us to manage our accounts activities, such as to calculate the taxes to generate the profit and loss reports, vouchers of all expenditures.
Computers also help us to manage our inventory and like accounts software, inventory softwares are also easily available about in the market and the stock remains always in front of our eyes. It helps us to take decision that what items are urgently required and where the items are over loaded. In short, our store stock and warehouse position always remains under our observation due to the computer.
Where computers help us to manage our accounts and inventory it is also very useful as for as the sale is concerned. If a factory has more than one outlet (shop) in one or different cities. We can update our daily sales with the help of computers. We can replicate the data from sales point and in this way our main database updates. The sales man puts the amount of all items and this one time activity prevents him to calculate again and again the list of sold items. Customers also receive the detailed printed receipt of items with the individual price items quantity, total amount and the grand total. Computer also calculates the taxes and all is easily possible due to the use of computer.
So, in the end, we can summarize our post that computer is very vital invention of last century. Prior, the invention of computer it was too much difficult task to manage our data but with the help of computer, it has become too much easy to manage our day-to-day activities in all fields of life. In this post, we discussed the use of computer in our business. We can save the adman’s related records such as the information of employees leave record; we generate the monthly payrolls and all the records related to payrolls such as salaries, salaries taxes and benefits.
Computer is also very useful in the accounts department and helps us to manage account records, it helps us to calculate profit and loss reports and generate accounts ledgers. Computers help us to maintain our inventory system, to maintain our store and warehouse stock positions and in the end we discussed how computers help us as for as the sale is concerned. In our future posts we will look that how it is useful in the other fields of life.

Friday, February 22, 2008

The Communication Medium

Before writing about the communication media, I would like to explain some terms or definitions related to data communications. When we talk about he data transmission, there are two types of transmissions. One is called serial transmission and second is called parallel transmission. As shown by the name, in serial transmission data transmitted on bit by bit. At a time only one bit will transmit whereas on the other hand when we talk about the parallel transmission data transmitted in sets of 8, 16 or 32 bits at a time. So, the parallel transmission is much faster as compare to the serial transmission but we use this parallel transmission only for short distances but when we want to transmit data long distance then the serial transmission is recommended.
Now, we come to our post title “the Communication Media” media is a source which, we use to transfer data from one place to another or in other words we can say that when we transfer data from one place to another place, we must use some sources to transfer data from one place to another place, we must use some sources to transfer it, these sources are called the “Communication Media”, Furthermore, these media has further two categories, Guided Media and the Unguided Media. When we use some physical media for our communication such as cables that is called guided media. On the other hand when our data transfers through some non-physical resource, this is called unguided media. The unguided media only used as a medium for data traveling, and not guide the signals towards any specific path that’s why this called unguided media. Microwave transmission and the satellite communication are its examples. When we talk about the microwave transmission, it is high-speed data transmission media but in this media we have to face little problem that signals travel only in straight lines so, we have to use microwaves antennas on a very high place to avoid the earth curvature. The 30 miles height for microwave antennas is recommended. These antennas receive signals from the previous antenna and then transmit it to the next antenna. Satellite communication is another form of unguided media. In these media two things involves. First, earth station and second satellite station. The earth station throws the signals to the satellite station, which is almost 23,000 miles to 24,000 miles above the earth that satellite station boosts up the signals and then transmit them to another earth station. So, these were the examples of unguided communication media. Now we will talk about the guided media
When the signals use some physical media for communication or when the signals travel through some physical media, this is called Guided Media. The following are the examples of Guided Media.
Coaxial Cable
Coaxial Cables are recommended within the range of one Kilometer or for the local area network. It is a copper wire that surrounded by the insolating material
Twisted Pair
These are the Cables of thin diameter, in the form of twisted pairs but it is not as reliable as the Coaxial Cable
Fiber Optic Cable
This is the fastest medium and it consists of hundred of thin glass. It also provides the high security level but it has also a disadvantage that it cannot support for the long distances.

Sunday, February 10, 2008

Modes of Data Communication

When we talk about the data communications. It involves the communication of data between two devices, mostly between the computers and sometimes other devices like cell phones, radio and T.V etc. the data travels in some particular direction or in other words, I can explain that when any data communication activity performed, there involves sending devices and receiving devices and the data, which, is being communicated, travels from sender to receiver. So, the direction in which the data travels is called “Data Communication Mode”. This data communication mode has following types.
Simplex Mode
In simplex mode type, the data travels in only one direction and there is no possibility to change the direction of data. In other words, we can say that the direction of data will always be same between the two communicating devices. The device which is receiving the data (Receiver) cannot send the data in reply, were as on the other hand the sender will always send the data and cannot receive the data in reply. So, we can say that in simplex mode of data, the data always travels in only one direction and that direction is from sender to receiver.
Half-Duplex Mode
The second type of data communication mode is “Half-Duplex Mode”. In this type the direction of data could be towards the both sides. I mean to say that data travels from sender to receiver and the receiver, in response can also send the data to sender. We can understand this Half-Duplex Mode further by the example of a server and client communication. We have a database on server and on the other hand we have a client computer. Now from the client side we send a query to server where we ask for all the records employs having the grade three. So, when we write the query on the client computer and send it to the server, the direction of data is from client to server, in response of this query, server sends all the records (data according to query) to client computer. Now, the direction of data is from server to client. So, the data direction of data is in both directions, first from client to server, then from server to client. The further important point of Half-duplex Mode is it, that though, the data ravels in both directions but at a time data can travel in only one direction, when the activity is completed in one direction, then second activity will start in other direction. In short, we can say that data cannot travel in both directions simultaneously. Though, the direction of data could be change. Half-Duplex mode is better than the Simplex Mode, but it is not a quick communication mode because the device will have to wait to change the direction until the communication in one direction is completed.
Full-Duplex Mode
The third and the speediest type of data communication mode is the Full-Duplex Mode. In this type data can be travel in both directions at a time. The sender can be receiver as at a time and the two devices send and receive data simultaneously. So, the Full-Duplex mode is the faster mode as for as the data communication modes are concerned.