There was only one usage earlier-sugar less or without sugar. The diabetics used to take coffee, tea and other food and beverages without sugar.Those prone to diabetics or those who were calorie conscious took some earlier precautions and consumed sugarless items; i.e. they used sugar less than the normal satisfying quantum.
It is after a particular brand of artificial chemical sweetener brought out in the market that the word sugar free became popular. That particular brand item contained a chemical which was giving sweet taste to the food and beverages to which it is added even in small quantities, but that is not sugar in its chemical combination nor has the calories or carbohydrates white sugar has. There were artificial sweeteners even before this particular brand, but they were not advertised in that way but used the name of the ingredient.
Then the word Sugarfree became very popular and even sweet manufacturers and manufacturers of refreshment drinks also started using the word sugarfree. The main ingredient in the brand sold as Sugarfree is Sucralose which is also actually derived from normal sugar by chemical process. It is the result of removing the hydroxyl (Oh) part from the sugar and replacing it with Chlorine(Cl).
The sucralose is consumed in comparable very less quantity to sugar for equivalent sweet taste. Unlike sugar, sucralose is not absorbed by the body and is excreted directly without break up. Any minute absorption is also excreted by urine.