Letter P
A packet is a self-contained bundle of data sent over a packet-switching network. Packets are typically less than 1500 bytes in size. Longer files are broken into multiple packets for transmission and reassembled at the other end. A packet includes a header with to and from addresses, relation to other packets (sequencing), and error-checking information. On the Internet, datagram is a synonym for packet. See TCP/IP.
page
- (verb) To call somebody electronically. With telephone service, when you page someone, that person’s pager activates and sounds an alarm. With the Internet, a page is usually a call to chat, and will pop up a window on the recipient’s desktop.
- (noun) A document displayed on the web. A page may consist of a single screen or multiple screens reached by scrolling down or to the right.
palette
The set of colors used in a picture or on a computer screen. Older computers typically used only 16 colors. Modern ones use at least 256 colors, which can be coded by 8 bits of information. With advanced color cards and monitors, 65.5 thousand colors (16-bit) or 16 million colors (24-bit) are used. Different web browsers and computer platforms do not necessarily use identical palettes. There is a set of 216 colors that are considered browser and platform safe, which web page designers should use, if they want screens to look essentially the same on each computer that views them. See Web Safe GIF Colors, Dithering, and Anti-Aliasing for more help with this.
PDF
Adobe’s Portable Document Format. It is often used as a format which allows much more complete, controlled layout of a page and its graphics and text than conventional HTML does. It requires a browser plug-in to see a web page in PDF format. Files will usually have a .pdf extension.To create a page in PDF format, you need Adobe Acrobat (not the free Acrobat Reader) or other premium Adobe software.
PGP
Pretty Good Privacy, Phil Zimmerman’s pioneering encryption software that successfully defied government restrictions and won him many awards. PGP is now part of Network Associates, where you can learn more and get the software.
PICS
Acronym for Platform for Internet content Selection, a model for associating labels with content in header metadata, originally devised to help parents and teachers and filtering software control children’s access to the net. See the World Wide Web Consortium (W3C) PICS Page for further information.
Packet InterNet Groper. An Internet utility used to check the connection with another site. It repeatedly bounces a signal off the remote site and shows you how long it took to complete the round trip each time. If you get no returns at all, the site is either down or unreachable. If only a portion of the signals are returned, it indicates some trouble with the connection that will slow down performance. You can run PING software on your own system with a PPP or net account, or you can use it as a command from Delphi’s NavNet textside Utilities menu and from most shell accounts. See traceroute.
pixel
One dot on a computer screen. Today’s least expensive monitors typically are 640 pixels wide and 480 pixels high. Larger and more expensive monitors range up to 1600 x 1200 pixels and special purpose monitors may go much higher than that.
Usenet speak for “You’re in my kill file, bozo!” Supposedly the sound of a newbie falling to the bottom of a kill file. See bozo filter.
plug-in
A piece of software that plugs into a main program to give it added capability, for example, you can add a Quick Time plug-in to your browser to play Quick Time movies on the web.
PMFJIH
Shorthand for Pardon Me For Jumping In Here. Often used in chat and messages as a polite excuse to enter the discussion.
Portable Network Graphics. A graphics format designed as the successor to GIF. It features compression, transparency, and progressive loading, like GIF, but it is free of patent restrictions. It is supported by most current browsers, beginning in 1997. If you see the graphic above at the right, your browser supports it. Current versions of Netscape and MSIE support it. See the PNG Home Page for further information
Ponzi scheme
A money-making pyramid scheme where investors at the top of a list of names make money by recruiting more investors into the scheme. Those at the top are paid by the fees gathered from recruits up to 5 or 6 levels down. Ultimately, those at the bottom lose their money when they run out of new recruits. It has many variations and is illegal in most countries. See a Statement by the FTC for more.
POP
Post Office Protocol. A protocol for client-server e-mail systems. If you are using software like Eudora or Pegasus or the mail clients in Netscape or MSIE, your address to collect mail often will begin with pop. For example, Delphi e-mail accounts use an address of pop.delphiforums.com to collect mail. See SMTP and IMAP.
port
1. A connection to a computer to enable other devices, such as printers, modems, monitors, keyboards, mice, etc. to interface with the computer.2. A logical connection to a network. Different port numbers are used for different purposes, for example, HTTP usually uses port 80. See List of Common Port Numbers
portal
A gateway or entrance to the web. In common usage it has come to describe a starting point page with a hierarchical, topical directory, a search window, and added features like news headlines and stock quotes.
POTS
Acronym for Plain Old Telephone Service.
PPTP
Point to Point Tunneling Protocol. A new technology developed by Microsoft, US Robotics, and others to enable Virtual Private Networks (VPN) to work securely over the Internet without exposing their communications to intercept. It is currently available only to Windows NT and linux networks. As of June 2, 1998, security flaws have been revealed in Windows NT, which make it much less secure than previously believed. Security patches are expected.
privacy
A source of concern to many on the Internet is how much personal information on them is available to all who look for it. Wherever you open an account on the Internet and World Wide Web, you are asked for personal information. What happens to this information? Do you have a rignt to privacy? See our article on Privacy: What Can Others Learn About You?.
protocol
A standard for the exchange of information. Different computers and operating systems and software are able to communicate with each other on the Internet, because of the adoption of protocols.
proxy server
A proxy server is a process that acts like a switchboard through a firewall to manage the various types of permitted communications with the outside world. Proxy servers may also use caching to make communications more efficient.
push
The technology that puts pre-selected content directly on your computer screen from the Internet without your need to browse for it. With this technology, introduced by PointCast and Individual, Inc.and added to 4th generation browsers, you can program your desktop, for example, to automatically receive such things as local weather, news headlines, selected stock reports, and sports scores for selected teams or events.