<s>[INST] How to check which version of Spark do I have? [/INST] To determine which version of Spark you have, you can use the following steps:
    1. cd to $SPARK_HOME/bin.
    2.  Launch spark-shell command.
    3. Enter sc.version or spark.version.
I hope this helps</s>\ <s>[INST] What do you mean by `cd`? What does `$SPARK_HOME` mean? Where should I type these lines? [/INST] `cd` is the command in the UNIX operating system, and later its open-source offspring, Linux and its many distributions. It's used to change the current working directory. The "cd" stands for "**c**hange **d**irectory". It is one of the most frequently used commands in the Linux terminal.

`$SPARK_HOME` is the environment variable for Spark. This needs to be set so that OS knows where to find Spark.</s>\ <s>[INST] What is the significance of the "$SPARK_HOME" environment variable in Spark? Why is it necessary to set it? [/INST] 