A variable is a symbol, commonly a single letter, that represents a number, called the value of the variable, which is either arbitrary, not fully specified, or unknown. Scientists try to figure out how the natural world works. In doing so, they use experiments to search for cause and effect relationships.
In a space, what are those variables? Furniture on the floor, walls beside us, and people in the room are all variables. Their role constantly changes between dependent and independent variables. Sometimes one single object could be a confounder, which influences both the dependent variable and the independent variable, causing a spurious association.
Turn off the light and turn on Variables. Lie down and take a look at the light effect on the ceiling. What are the variables in this room? Hmm, maybe… I… am……zzz