What kind of dressing is in potato salad,,?

Mayonnaise.

Mayonnaise is light yellow in color, moderately soft, viscous, with a certain toughness, crisp and refreshing, with a strong aftertaste. The water-phase part comes into contact with the tongue first when consumed, so it first gives a smooth, refreshing sense of sourness before the oil-phase part can be detected. Add tomato juice, green peppers, pickled cucumbers, onions, etc. to make a sauce for fresh vegetable salad or macaroni salad.

Mayonnaise Origin:

In countries such as the United States, Western Europe and Japan, mayonnaise is as common as Chinese condiments such as noodle sauce and bean paste. Mayonnaise originated in Europe. Medieval European culinary masters separated egg whites and yolks.

Then gradually add olive oil, and then add refined salt and lemon juice, it becomes a creamy, thick sauce for making and decorating various salads, which is mayonnaise. In the late 19th century, many European cuisines were introduced to China, and with them came mayonnaise.