A BRIEF INTRODUCTION TO UNIX OPERATING SYSTEM Huifeng Shao $1. Operating System and UNIX (a). General Operating System (b). UNIX Operating System $2. The Feature and Architecture of UNIX (a). Features (b). Internal Structure $3. UNIX Comparing with Other Operating System $4. UNIX Market

$1. Operating System and UNIX (a). What is an Operating System? Operating System is a necessary tool for using a computer to run application programs.

$1. Operating System and UNIX (b). UNIX Operating System Unix Operating System is more than an operating system in traditional sense. Unix system includes a set of libraries and a set of applications. General functions of UNIX System includes: Providing system service Providing a user interface Coordinating the sequence of events Controlling resources Enforcing security Providing tools

$2. The Feature and Architecture of Unix (a). Main Feature Multiuser Capabilities: UNIX enables more than one person to user the computer at the same time through a process called “TIME-SHARING” Advantages: (1). Low cost per user; (2). Central administration; (3). Shared resources Multitasking Capabilities: UNIX can perform more than one task at a time for each user. Advantage: greatly increases productivity Device Independence: UNIX enables you to use files and devices interchangeably. Advantage: much easy to move data to and from files or devices Portability and Open System: It’s the most notable feature. Unix has capability to run on a wide range of different computer makes and models (open system). No other operating system even approaches this level of portability. Advantages: (1). Almost no cost to convert to a new system (little/no training and minimal effort of converting data and software); (2). Interoperability between systems, e.g. application programs can be written once and versions made available for all kinds of machines. The Tools Approach: UNIX has hundreds of small, build-in programs called TOOLS, each of which accomplishes a common, simple task. You can accomplish complex tasks by combining tools in various ways. Advantage: (1). Flexibility; (2). Speed; (3). Structured approach

$2. The feature and Architecture of Unix (b). Internal Structure

$4. UNIX Market