Mayonnaise is an emulsion of fat and oil, with the fat being egg yolks, along with an acid such as vinegar or lemon juice. Salt is added and often other seasonings. By law, mayonnaise must be 65% oil by weight and the emulsifier must be egg. It's easy to make at home, but most people, me included, rely on the commercial product (don't get me started on Hellman's vs. Duke's!).

Miracle whip, on the other hand, is classified as a salad dressing. The main three ingredients are water (yes, water), soybean oil, and high-fructose corn syrup. Eggs are further down the list and spices are included also. It was developed in 1933 as a less expensive alternative to mayo and has become very popular. But mayo it is not.