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IMR Glossary

This page has a limited set of definitions related to the Internet Medical Record. For terms not listed here see the CNet Glossary of Computer Terms (less technical) and the Computing Dictionary (more technical). indicates a link outside of this document elsewhere on this site or the web. Glossary - Introduction to the Internet includes some more basic terms.

Berners-Lee, Tim

The man generally considered to be the creator of the World-Wide-Web at CERN in Switzerland. He did not become wealthy from his creation, but neither did Guttenberg.

 

Client/Server

Originally this term was applied to two-tiered applications that put the user interface on one machine, a database on another, and divided processing between the two. Now it's applied more broadly to distributed applications which may include multiple databases, multiple processing and transaction centers, and a client which holds the user interface. In modern multi-tiered Client/Server applications processing may move between client, server, and middleware as needed.

 

Common Gateway Interface (CGI)

A standard way to for a web browser to communicate with a script or other application which may in turn manage databases or other system resources. CGI is character based and has a lot of overhead, but it is simple and robust.

 

Connection and State

See HTTP.

CORBA

Common Object Request Broker Architecture. CORBA on the web is mostly defined by three components: the IDL, IIOP, and CORBA services. The Object Request Broker (ORB) is the software that uses these components. CORBA is a standard for producing Client/Server middleware.

 

CORBA services

A suite of (currently 16) services that CORBA applications can (theoretically) use. Typical services include a naming service (names objects and stores their addresses, can connect up with LDAP directories as well), a persistence service (interface to persistent storage in databases), and a security service. CORBA services are still more theoretical than real.

 

EMR, CPR, CBPR, ACIS

These are all acronyms which refer to more or less the same thing. EMR stands for electronic medical record, CPR for computerized patient record, CBPR for computer-based patient record, ACIS for ambulatory care information system. In each case the terms refer to computerized systems that assist at least in documenting clinical care and often in supporting clinical work.

 

HTML

HyperText Markup Language. The standard used to create documents that web browsers (Netscape, Internet Explorer) can interpret. Standard HTML is defined by the W3 Consortium. Netscape and Microsoft have created proprietary extensions to HTML.

HTTP

HyperText Transfer Protocol. The standard for sending HTML and other web content between a web browser (Netscape) and a Web Server. HTTP 1.0 is a stateless protocol; the web server has no simple way to know the status of the client (web browser). HTTP is also sometimes (confusingly) called connectionless, meaning that it the client browser is only connected to the server for brief intervals. HTTP 1.0 connections also require quite a bit of overhead, consuming server resources. Displaying a single web page may require many of these transactions. HTTP 1.1 addresses many of these problems. See W3C Recommendations Reduce World Wide Wait.

 

IDL

Interface Definition Language. A CORBA standard for describing an object -- what it does and how to use it.

 

Internet, Intranet, Extranet, Shmextranet

The Internet is the set of all computers and other devices that have IP addresses from the Internet naming authority, and that communicate with one another using "IP packets". Many people use the word Internet to refer to the collection of web information that is maintained on some of these machines.

 

An intranet is a private network that uses the same technology as the public Internet; but the machine addresses (IP) are private and the machines cannot directly communicate with the public Internet. An intranet may communicate with the Internet through a "firewall" machine.

 

Internet Protocol (IP)

The most basic (defining) foundation of the Internet. A way of naming things that are a part of the Internet, and the definition of an Internet packet (unit of transmitted information). IP is going to be replaced in time by IPv6 (also called IPNG). IPv6 will provide better security, a vastly increased ability to name things, and the ability to differentiate between high priority and lower priority network traffic.

Internet Inter-ORB Protocol (IIOP)

The standard way for ORBs to talk to one-another over the Internet. It's basically TCP/IP with some additional message exchanges.

 

Java

An interpreted programming language developed by Sun, paired with a platform-specific execution environment (Java Virtual Machine). Java resembles C, with some additions from C++ and Smalltalk. It's strengths as an Internet language come from its security model, class library, and its support across many platforms from a digital TV controller to a top level IBM mainframe.

 

JavaBeans

An emerging specification for Java based components that can be assembled to create applications.

Lightweight Directory Access Protocol (LDAP)

A standard way to create a directory of things, people,and services. LDAP is a simplified version of the x500 directory service. LDAP is one of those things that seems simple, but may be profoundly important. For references see LDAP references.

 

Loose Coupling

A way of describing systems that can be taken apart or revised without damaging the entire system. A human being is "tightly coupled", the human genome is "loosely coupled". Loose coupling permits adaptation, evolution, and extension.

 

Middleware

Everything that lies between the Client computer (ie. a Windows 95 workstation running Netscape) and the Server (ie. a UNIX server running Oracle). The original Internet middleware was a Web Server and some CGI programs (often written in Perl; a programming language that excels at handling the strings that CGI uses).

 

Network Computer

A computer which relies upon the network for its functionality and uses Internet technologies, especially including Java and HTML. Current Network Computers typically run a web browser and support Java. Major backers of Network Computing include Sun, Oracle (Network Computer Inc.), IBM and Netscape and all CPU vendors who are not Intel. Microsoft has been a bit less enthusiastic. The NC Reference Profile provides more detail. (See also Network Computers.) Despite the Microsoft vs. The World conflict, a Network Computer could in fact use Windows NT as its operating system, though it would not run Windows software other than a web browser.

 

Object Request Broker (ORB)

A component of the CORBA specification. The ORB does the work of establishing communications channels between objects (application components). Leading ORB vendors today include Visigenic's Caffeine (Netscape 4.0 includes Visigenic's ORB), Iona's Orbix and Sun's JOE (JOE is written in Java).

 

Perl

A programming language that is exceptionally good at parsing and managing strings and streams. It has been heavily used in industrial web applications.

 

Sutton's Law

Willie Sutton was an unsuccessful bank robber. It is said he was asked why he robbed banks. He replied: "Because that's where the money is". The story is apocryphal, but it's a classic nonetheless.

TCP/IP

The language spoken by the computers that make up the Internet. TCP/IP is the "roadway" upon which email, web exchanges (http), and other net traffic travels. Its components are IP and TCP (error correction). "I don't know what protocol the network of the future will use, but it will be called TCP/IP." (anon)

 

Thin Client

Term given to computer platforms (hardware and software) that hold a minimal set of software and data locally. These platforms get their software and data from network servers as needed. The central storage and automated distribution of data and applications dramatically decreases the Total Cost of Ownership (TCO). It also allows a one or more users to work with multiple devices at many locations with one set of data and applications. A thin client is typically one tier of a Multi-Tier architecture. The Network Computer is one type of thin client.

Tiered, Multi-Tier, Three-Tier Architectures

Client/Server computing can be described in terms of the division of labor between the user's computer at one end, and one or more databases at the other. Two tiered systems have two levels -- client and server. Three tiered have client, server, and middleware. Sometimes other tiers are added in, but, practically speaking, three-tiered is often taken to mean "multi-tiered".

 

Total Cost of Ownership (TCO)

TCO refers to the total cost of owning and operating a computing platform. This is typically much higher than the purchase cost of hardware and software; it includes the cost of training, upgrades, maintenance, software distribution and installation, and depreciation.

 

URL

Uniform Resource Locator. A standard way of identifying and locating something on the Internet. http://jfhomepage is a URL that identifies and locates my web page.

 

W3C or W3 Consortium.

The standards body for the World Wide Web. Specifies what is standard HTML based on its own work and on adjudicating Microsoft and Netscape extensions to HTML. Berners-Lee is an active leader.

 

Web Server

A networked computer and software that can receive HTTP requests (typically from a web client/browser, like Netscape) and return HTML (web pages). Web servers usually also support CGI connections to databases and other Server software. Next generation Web Servers support IIOP requests and can handle CORBA transactions too.

 

World Wide Web (WWW)

A term applied to a number of things which all together produce the Web.

• a collection of documents (web pages) written in a standard language with hyperlinks (HTML)
• a standard way to send messages (HTTP)
• a standard way to address web pages (URL)
• software/hardware that "serves" those documents (web servers)
• a network on which everything exists (Internet)
  

XML (Extended Markup Language)

A rapidly emerging specification for encoding machine-readable information. XML shares common roots with HTML, but it can encode information for both human and computer use.