Which is the command used for displaying the values of a variable into the output console or log? | Selenium

The command used for displaying the values of a variable into the output console or log - echo
If you want to display a constant string. The below mentioned command can be used
echo <constant string>
ex: echo "The sample message"
If you want to display the value of a variable it can be written like below
echo ${<variable name>>
ex: echo ${var1}
Note: Here var1 is the variable.