Expand your IT vocabulary

As you now know, the world of Information Technology is full of terminology.  While some of these terms may be confused by marketing "buzzwords" it is important that we understand them nonetheless.  This post will collect terms that I will use quite frequently over the second half of the course.  If you would like to clarify your understanding of these, or any other terms, please comment here.

Software - logical instructions written in human readable languages and converted into machine code to effect an electronic process. 

Software Program or Software Component - a specific and discrete set of logical instructions written in human readable languages and converted into machine code to effect an electronic process.   The spell check feature might be a program or component within MS-Word.

Application - a software component or collection of components that is organized around a specific task or set of tasks.  MS-Word is a software application.

A distributed software application is one with two or more distinct components which can perform more or less autonomously (individually) and yet also interact together to perform an additional series of tasks together.

Web application - typically a software program or collection of software programs that take advantage of Web standards and protocols. Typcially they rely on browsers, web servers, and therefore http, URI, etc...

Database - a collection of information organized in such a way that a computer program can quickly select desired pieces of data. You can think of a database as an electronic filing system.

Database Management System (DBMS) or Relational Database Management System (RDBMS) - a software application that is designed to manage a database.

Server (software) - a software application that is dedicated to "serving" other software applications (typically referred to as clients).

Client - a software application that relies on a dedicated "server" to provide services.

User Interface (software)- software components whose purpose is to interact with human users. Also known as GUI (Graphical User Interface).

An Intranet is nothing more the a private network which behaves much like the Internet and the World Wide Web. Typically this internal network is protected from public use by security measures and for private memebers uses Internet protocols to route information and web applications to manage content.

A node is a generic name for a member of a network. A machine or a software applicaiton which belongs to a network might be called a node. A person might even be called a node though the more polite term is member.

Scalability basically means the ability to increase or decrease computing capacity. Often it is associated with growth in functions, data, or users. Systems like the Internet and the Web are incredibly scalable.

The front-end of an application typically refers to the user interface and its related parts.

The back-end of an application typically refers to all other components of a software system, particularly the database and its related parts.

In a 3-tier system, between the database and the user-interface or presentation layer as it's commonly called lies the application logic which performs independent functions (like computations, routing, etc..) and provides services to both front and back-end applications. The middle layer, aka the application server, is where most of the application logic lies. This is what drives the software and coordinates the database and the user interface.

Client and Server are two terms that refer to their role and purpose in an exchange of services. A Server provides specialized services to a Client upon request. A client/server architecture is an architecture in which processing and storage tasks are divided between two classes of network members: clients and servers.

Logical and Physical are terms are two terms that refer to the nature of the environment in which they exist.  There is a difference between a physical line, say a straight highway, between two points, and the notion of the shortest distance between two points. One is a physical instance of a line.  And one is a logical construct...which makes sense and bears relevance to our physical world even if it is just a thought.   Hardware is tangible and exists in a physical world. Software is intangible and exists virtually in a logical world. Though we don't see it in action we know logically what software can do by using conceptual models and measuring its results and performance.   

A Platform refers to a set of components which share or depend on the same infrastructure or operating environment and therefore are interoperable.  Other words like environment, system, may be used to describe to say the same thing.