While there is no such thing as 'Sugar Free' in real life, many manufacturers claim their products are Sugar Free. This probably should read that no additional sugar has been added while manufacturing the product; it is common knowledge that all carbohydrates are converted into sugar by the body. If a recipe calls for the use of sugar, many manufacturers use Sucralose, Aspartame, Saccharine or other sugar substitutes that are readily available. While this satisfies the legal labelling requirement, products that are labelled Sugar Free may not be any healthier than those that contain sugar, nor taste any better!
Products that are Sugar Free are indicated by this icon in the product detail page: