Bash Shell Scripting- what is #!/usr/bin/env bash ?

The video tutorial explains the concept of the shebang line in shell scripts and its importance in determining which shell to use for execution. It highlights the differences in bash shell paths across various operating systems like Ubuntu and RHL, which can affect script portability. The tutorial introduces the use of the ENV command to make scripts portable across different Unix and Linux systems by dynamically determining the correct path for the bash shell. The video demonstrates how to implement this solution, ensuring scripts run seamlessly on any system.

Explain how to make a shell script portable across different Unix or Linux systems.

What is the significance of using the 'env' command in the shebang line?