Elementary Computer Application
ELEMENTARY COMPUTER APPLICATIONS
Chapter 1: Information concepts and Processing
Information Data that is (1) accurate and timely, (2) specific and organized for a purpose, (3) presented within a context that gives it meaning and relevance, and (4) can lead to an increase in understanding and decrease in uncertainty.
Information is valuable because it can affect behavior, a decision, or an outcome. For example, if a manager is told his/her company's net profit decreased in the past month, he/she may use this information as a reason to cut financial spending for the next month. A piece of information is considered valueless if, after receiving it, things remain unchanged. For a technical definition of information see information theory.
2.10 Data Organisation
Data is organised before processing on a computer. Data can be arranged in a variety of ways, but a hierarchical approach to organisation is generally recommended. l Data Item
A data item is the smallest unit of information stored in computer file.
It is a single element used to represent a fact such as an employee's name, item price, etc. In a payroll application, the employee number 170 is a data item. PANKAJ the name is a data item. l Field
Data items are physically arranged as fields in a computer file. Their length may be fixed or variable. Since all individuals have 3 digit employee numbers, a 3-digit field is required to store the particular data.
Hence, it is a fixed field. In contrast, since customer's name vary considerably from one customer to another, a variable amount of space must be available to store this element. This can be called as variable field. l Record
A record is a collection of related data items or fields. Each record normally corresponds to a specific unit of information. For example, various fields in the record, illustrated in Fig. 2.4 are employee number, employee's name, basic salary and house rent allowance. This is the data used to produce the payroll
Chapter 1: Information concepts and Processing
Information Data that is (1) accurate and timely, (2) specific and organized for a purpose, (3) presented within a context that gives it meaning and relevance, and (4) can lead to an increase in understanding and decrease in uncertainty.
Information is valuable because it can affect behavior, a decision, or an outcome. For example, if a manager is told his/her company's net profit decreased in the past month, he/she may use this information as a reason to cut financial spending for the next month. A piece of information is considered valueless if, after receiving it, things remain unchanged. For a technical definition of information see information theory.
2.10 Data Organisation
Data is organised before processing on a computer. Data can be arranged in a variety of ways, but a hierarchical approach to organisation is generally recommended. l Data Item
A data item is the smallest unit of information stored in computer file.
It is a single element used to represent a fact such as an employee's name, item price, etc. In a payroll application, the employee number 170 is a data item. PANKAJ the name is a data item. l Field
Data items are physically arranged as fields in a computer file. Their length may be fixed or variable. Since all individuals have 3 digit employee numbers, a 3-digit field is required to store the particular data.
Hence, it is a fixed field. In contrast, since customer's name vary considerably from one customer to another, a variable amount of space must be available to store this element. This can be called as variable field. l Record
A record is a collection of related data items or fields. Each record normally corresponds to a specific unit of information. For example, various fields in the record, illustrated in Fig. 2.4 are employee number, employee's name, basic salary and house rent allowance. This is the data used to produce the payroll