Variable assignment. After R evaluates a calculation such as one plus three, the output of this is not stored anywhere. Four is displayed on the screen, however no record of this result is captured in the global environment. We can assign or store the value of the calculation with a label. We can utilise the assignment operator. I can assign the value of four to say for example the label X utilising the assignment operator, left arrow dash followed by the right hand side of the formula, which would have to include one plus three. Now, the value of three plus one, the result of the calculation being four, has been assigned to X as we can see in our global environment. 

Variable assignment is asymmetric, one plus three assigned to the value X would return an error. So the order of flow between the left hand side and the right hand side is critical. Can we use the equals symbol to assign a variable such as X equals one plus three? Yes, but this is rarely used. Best practice is to use the assignment operator. Can labels have dots as part of their names? Say for example I went to a restaurant and I had the option to split my bill, I can create three different variables for food, and by typing in the variable starting name on the screen I see a series of tab options available. So by pressing tab I get the first entry. I could type in dot and bring up the second entry. So by typing in the parameter name for the bill, I can follow it up and choose which one I'd like to return.

Labels are case sensitive. There is a difference between the two variables that I have just defined due to the capital I, the capital C and the capital S, as you can see in the global environment explorer. Can I list all of the labels that I have created in my workspace, or can I see them? I can use the LS command. Technically speaking, the LS command does not see a hidden variable, variables with a dot at the beginning are hidden. After having created a variable, can I remove it? I can use the RM command to remove it. So now if I type in LS again I will see that the food option has disappeared from the list. What if I'd like to remove all of the objects I have in my current working space? I can use the command RM list is equal to LS open brackets close brackets. This will remove all objects in my global environment.