What are local and global variables?

Local and global variables are terms used to describe the scope and accessibility of variables in programming.

Global Variables

• Definition: Global variables are defined outside of any function and can be accessed from any part of the program, including inside functions.
• Scope: They have a global scope, meaning they are available throughout the entire script or program.
• Example:

  GLOBAL_VAR="I'm global"
  
  function example() {
      echo $GLOBAL_VAR  # Accessing the global variable
  }
  
  example  # Output: I'm global

Local Variables

• Definition: Local variables are defined within a function and can only be accessed within that function.
• Scope: They have a local scope, meaning they are not accessible outside of the function where they are defined.
• Example:

  function example() {
      local LOCAL_VAR="I'm local"
      echo $LOCAL_VAR  # Accessing the local variable
  }
  
  example  # Output: I'm local
  echo $LOCAL_VAR  # This will not work; LOCAL_VAR is not accessible here

Summary

• Global variables can be accessed anywhere in the program, while local variables are restricted to the function in which they are defined. This distinction helps manage variable scope and prevents naming conflicts in larger programs.