Cake 10+6 means: it's a two-tier cake, the bottom tier is a ten-inch top, and the top tier is a six-inch, which visually feels like it's ten inches big.

Generally cake stores sell 6-inch, 8-inch as well as 10-inch cakes.

The sizes and the number of people who can eat them are:

6-inch: for about 2-4 people, suitable for birthday parties, Valentine's Day, Mother's Day and other festivals.

8 inch: 4-6 people serving, suitable for birthday parties, various festivals, visiting friends and relatives.

10 inch: 6-10 people serving, suitable for birthday parties, various festivals, visiting friends and relatives.

12 inch: 10-12 people, suitable for birthday parties, various festivals, visiting friends and relatives.

14 inch: 12-14 people, suitable for company, classmates gathering.

16 inch: 14-16 people serving, suitable for all kinds of medium-sized celebrations.

Multi-layer cake: the size difference between the upper and lower layers is at least 4 inches. For example:8 inches at least stack 12 inches, but not 10 inches.

Cake is an ancient pastry, usually made by the oven, the cake is made with eggs, sugar, wheat flour as the main ingredients. Milk, juice, milk powder, spices, salad oil, water, shortening, baking powder as auxiliary ingredients. After mixing, modulation, baking to make a kind of sponge-like confectionery.

A cake is a type of pasta, usually sweet, typically made by baking. The main ingredients of a cake include flour, a sweetener (usually cane sugar).

Binders (usually eggs, vegans can substitute gluten and starch), shortening (usually butter or margarine, low-fat cakes will substitute fruit juice concentrate), liquids (milk, water, or fruit juice), flavors, and leavening agents (such as yeast or baking powder).

Source for the above: Baidu Encyclopedia-Cake