How are variables accessed (e.g., printed) in a shell script?

In a shell script, variables are accessed (or printed) by prefixing the variable name with a dollar sign ($). Here are some examples of how to access and print variables:

1. Basic Variable Access:
   To print the value of a variable, you can use the echo command:

   my_variable="Hello, World!"
   echo $my_variable  # Output: Hello, World!

2. Using Variables in Strings:
   You can include variables within strings:

   name="Alice"
   greeting="Hello, $name!"
   echo $greeting  # Output: Hello, Alice!

3. Accessing Variables in Commands:
   Variables can be used as arguments in commands:

   file_name="example.txt"
   touch $file_name  # Creates a file named example.txt

4. Using Curly Braces:
   For clarity, especially when concatenating variables with strings, you can use curly braces:

   name="Bob"
   echo "Welcome, ${name}!"  # Output: Welcome, Bob!

5. Accessing Environment Variables:
   You can also access environment variables in the same way:

   echo $HOME  # Prints the home directory of the current user

These methods allow you to effectively access and print the values of variables in shell scripts.