The word Scotch on your favourite bottle of whisky, means that the whisky was produced, matured, and in the case of single malt whisky, bottled in Scotland. The term is a "protective designation of origin" which prohibits producers from using the term unless they meet the necessary criteria.
If your whisky has the word single in it, it denotes the fact that it is the product of a single distillery. If it isn't from a single producer, it will be a blend which is the result of blending whiskies from two or more distilleries.
Lastly, the term malt indicates that the whisky is made from 100% malted barley, distilled in copper pot stills and matured for at least three years. If it is not made exclusively from malted barley and/or it is distilled in continuous stills, then it is classed as a grain whisky. If the whisky does not stipulate malt or grain, it will be called a blended whisky, meaning it is the product of blending malt(s) and grain(s).