What term describes the ideal foam that forms on top of beer?

The term that describes the ideal foam that forms on top of beer is "head." The head is significant because it not only enhances the aroma of the beer, allowing the drinker to appreciate its bouquet, but it also plays a role in the overall mouthfeel of the beer. A well-formed head can contribute to the beer's appearance and is often an indicator of its freshness and carbonation levels.

Brussels Lace, while related to beer, refers to the lacing that traces the inside of the glass as the beer is consumed, which is a result of the head's retention on the glass. Cream is a term used less specifically in the context of beer foams, often referring to a thick, smooth foam found in other beverages, and froth, while similar, generally describes a less stable foam that may not indicate a beer's quality as effectively as a proper head. The head is critical in beer presentation and enjoyment, making it the most accurate choice for describing the ideal foam that forms on top of beer.