What is the difference between the spark-shell and spark3 command-line interfaces?

"What are the key differences between the spark-shell and spark3 command-line interfaces? How do their functionalities and usage differ, especially considering that Spark 3 introduced new command names to avoid conflicts with Spark 2? Are there specific features or improvements in spark3-shell that are not present in spark-shell? Additionally, how do the environments and variable setups differ between the two interfaces?"

Here are the key differences between spark-shell and spark3-shell:

Key Differences Command Names: Spark 3 introduced new command names to avoid conflicts with Spark 2. For example, spark-shell is used for Spark 2, while spark3-shell is used for Spark 3.

New Features: Spark 3 includes several new features and improvements that are not present in Spark 2. These enhancements are reflected in the spark3-shell interface.

Environment Setup: The environment setup and variable configurations might differ between the two shells due to the new features and changes in Spark 3.

Functionalities and Usage Spark 2 (spark-shell): This is the interactive shell for Spark 2, used for Scala, Python, and R. It provides a REPL (Read-Eval-Print Loop) environment to quickly test Spark commands2.

Spark 3 (spark3-shell): This is the interactive shell for Spark 3, also supporting Scala, Python, and R. It includes new functionalities and improvements introduced in Spark 33.

Environment and Variable Setup Spark 2 (spark-shell): Uses environment variables and configurations specific to Spark 2.

Spark 3 (spark3-shell): Uses updated environment variables and configurations to support new features in Spark 3.