Lesson 1-Logging On to the System

Overview Importance of UNIX/Linux. Logging on to the system.

Importance of UNIX/Linux Most Internet servers and all the fundamental computing structures run on UNIX/Linux systems. Most communication networks run on UNIX/Linux systems. The general infrastructure for communications, programs, smart devices, and critical data is managed on UNIX/Linux systems.

Importance of UNIX/Linux Records, research, communication, development, and publications depend on applications provided by UNIX/Linux systems. File serving for desktops, , and an enormous portion of publishing run in UNIX/Linux environments.

Logging On to the System The UNIX system’s ability to serve multiple users at a time is one of its primary features. A unique account associated with a login name is created when an administrator adds a new user to a system.

Entry to the UNIX system is granted only if the user provides a login name and a password that match an established user on the system. A user having a ‘root’ login is granted the extensive powers needed to administer the system. Logging On to the System

Character Window Log On Screen

Logging On to the System Terminal Window Log on Screen

Logging On to the System Ensure that the username and password is entered using the correct character-case, since UNIX/Linux is case- sensitive. In most systems, the login name and the password are in lowercase letters. Passwords are not displayed on the screen.

Care should be taken to avoid typing mistakes. Confusion between similar looking characters should also be avoided. For example, the alphabet O and the number zero (0). Logging On to the System

Terminal Window interaction Graphical Window interaction

Terminal Window Interaction Terminal Window Screen

Terminal Window Interaction The “date” command is used to display the current date and time. The “exit” command is used to log off from the terminal environment.

Graphical Window Interaction Graphical Window Screen

Graphical Window Interaction Logoff in Graphical Window Interface

Summary A valid username and a password are required to access a UNIX/Linux system. The root user has the extensive powers needed to administer a UNIX/Linux system. A user can log in from the terminal Window or the graphical Window.