Prerana Nawar Thanks for the information: 'undefined' means waiting for it to be defined, which may or may not assign other( other then defalut value : undefined) value in future. However, during memory allocation, the memory is allocated for it. On the other hand, 'not defined' is a reference error because memory space is not allocated for it, and we did not even declare the variable.

thanks bhai Ashwin Padiyar

What is the difference between shell scripting AND BASH SCRIPTING 🤔

Thanks dude