Owens FAQ
print  Print
Glossary

A
B
C
D
F
I
K
L
M
O
P
R
S
V
W
All

  • Daemon
    The word "daemon" actually comes from the Greek language, meaning an "inner or attendant spirit" (Oxford American Dictionary). This is a fitting name, as a computer daemon is a constantly running program that triggers actions when it receives certain input.

    For example, a printer daemon spools information to a printer when a user decides to print a document. A daemon running on a mail server routes incoming mail to the appropriate mailboxes. Web servers use an "HTTPD" daemon that sends data to users when they access Web pages. While daemons were first used by the Unix operating system, they have also been incorporated into Mac OS X, which is Unix-based.

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
     
  • DBMS
    Stands for "Database Management System." In short, a DBMS is a database program. Technically speaking, it is a software system that uses a standard method of cataloging, retrieving, and running queries on data. The DBMS manages incoming data, organizes it, and provides ways for the data to be modified or extracted by users or other programs.

    Some DBMS examples include MySQL, PostgreSQL, Microsoft Access, SQL Server, FileMaker, Oracle, RDBMS, dBASE, Clipper, and FoxPro. Since there are so many database management systems available, it is important for there to be a way for them to communicate with each other. For this reason, most database software comes with an Open Database Connectivity (ODBC) driver that allows the database to integrate with other databases. For example, common SQL statements such as SELECT and INSERT are translated from a program's proprietary syntax into a syntax other databases can understand.

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
  • DFS
    Stands for "Distributed File System." A DFS manages files and folders across multiple computers. It serves the same purpose as a traditional file system, but is designed to provide file storage and controlled access to files over local and wide area networks.

    Even when files are stored on multiple computers, DFS can organize and display the files as if they are stored on one computer. This provides a simplified interface for clients who are given access to the files. Users can also share files by copying them to a directory in the DFS and can update files by editing existing documents. Most distributed file systems provide concurrency control or file locking, which prevents multiple people from editing the same file at the same time.

    There are several types of DFSes, though some of the most common implementations include Server Message Block (SMB), Apple Filing Protocol (AFP), and Microsoft's Distributed File System (often called "MS-DFS" or simply "DFS"). DFS is included as a standard component of Windows Server, while SMB is typically installed on Linux machines.

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
  • DHCP
    Stands for "Dynamic Host Configuration Protocol." A network server uses this protocol to dynamically assign IP addresses to networked computers. The DHCP server waits for a computer to connect to it, then assigns it an IP address from a master list stored on the server. DHCP helps in setting up large networks, since IP addresses don't have to be manually assigned to each computer on the network. Because of the slick automation involved with DHCP, it is the most commonly used networking protocol.

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
  • Direct3D
    Direct3D is an application program interface (API) developed by Microsoft that provides a set of commands and functions for manipulating 3D objects. By using Direct3D commands, software developers can take advantage of many prewritten functions. This allows programmers to write significantly less code than if they had to write all the functions from scratch. Direct3D makes it relatively easy to manage three-dimensional objects, including lighting and shadows as well.

    In order for a software program to use Direct3D commands, the computer's video card or graphics accelerator device must support Direct3D. Fortunately, just about all video cards made for PCs offer Direct3D support. While many video games and other programs use Direct3D, OpenGL is a more widely used standard.

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
     
  • Directory
    A directory is another name for a folder. Files on your hard disk are organized into various folders, or directories, so that it is easier to keep track of them. For example, you may keep your pictures in one folder and your music files in another folder. Folders can also contain other folders, allowing for more specific organization.

    Since you can have folders within a folder, files on your hard drive are organized much like branches on a tree. The main directory on your hard drive is appropriately called the "root directory." Folders that exist within the root directory most likely contain other folders, which may branch out to even more folders.

    When you are browsing one directory and want to open the folder that contains the current directory, it is called "moving up a directory." As you move up directories, you will eventually move up to the root directory. In Windows, this may be your C:\ directory, while on the Mac it will be the name of your hard drive, such as "Macintosh HD."

    Tech Terms Dictionary 2014. Per Christensson. 7 April 2014. http://www.techterms.com
     
  • DNS
    Stands for "Domain Name System." The primary purpose of DNS is to keep Web surfers sane. Without DNS, we would have to remember the IP address of every site we wanted to visit, instead of just the domain name. Can you imagine having to remember "17.254.3.183" instead of just "apple.com"?

    The reason the Domain Name System is used is because Web sites are acutally located by their IP addresses. For example, when you type in "http://www.adobe.com," the computer doesn't immediately know that it should look for Adobe's Web site. Instead, it sends a request to the nearest DNS server, which finds the correct IP address for "adobe.com." Your computer then attempts to connect to the server with that IP number. DNS is just another one of the many features of the Internet that we take for granted.

    Tech Terms Dictionary. April 2014. Per Christensson. http://www.techterms.com