(1) A space allocated for a particular item of information. A tax form, for example, contains a number of fields: one for your name, one for your Social Security number, one for your income, and so on. In database systems, fields are the smallest units of information you can access. In spreadsheets, fields are called cells.
Most fields have certain attributes associated with them. For example, some fields are numeric whereas others are textual, some are long, while others are short. In addition, every field has a name, called the field name.
In database management systems, a field can be required, optional, or calculated. A required field is one in which you must enter data, while an optional field is one you may leave blank. A calculated field is one whose value is derived from some formula involving other fields. You do not enter data into a calculated field; the systemautomatically determines the correct value.
A collection of fields is called a record.
(2) The phrase in the field refers to any geographical location other than the factory or office where a product was created. Similarly, a field representativeis an employee who represents a company in distant locations.
(3) In video terminology, a field is one of many still images that make up a moving picture. A field is similar to a frame, but is displayed twice as fast and is half the vertical resolution.
(n.) A collection of data or information that has a name, called the filename. Almost all information stored in a computer must be in a file. There are many different types of files: data files, text files , program files, directory files, and so on. Different types of files store different types of information. For […]
- File Allocation Table (FAT)
A table that the operating system uses to locate files on a disk. Due to fragmentation, a file may be divided into many sections that are scattered around the disk. The FAT keeps track of all these pieces. In DOS systems, FATs are stored just after the boot sector. The FAT system for older versions […]
- file compression
See under data compression and packed file.
- file format
A format for encoding information in a file. Each different type of file has a different file format. The file format specifies first whether the file is a binary or ASCII file, and second, how the information is organized.
- file handle
A number that the operating system assigns temporarily to a file when it is opened. The operating system uses the file handle internally when accessing the file. A special area of main memory is reserved for file handles, and the size of this area determines how many files can be open at once. In DOS […]