Terminals are a link to shells.
User, Group and Others can have permissions to read write or execute a file / directory
Output of commands can be redirected to files. Files can be used as input to commands.
Working with variables and expansions on the shell.
For and While loop in Shell Scripting.
Process creation, killing processes. Signals such as SIGINT are also covered.
A regular expression, commonly called a “regexp”, is a sequence of characters that define a search pattern. It is mainly for use in pattern matching with strings, or string matching (i.e. it operates like a “find and replace” command). While it is a very powerful tool, it is also very dangerous because of its complexity.
OSI (Open Systems Interconnection) is an abstract model to describe layered communication and computer network design.
- Bash Scripting