Butter
Butter is made from milk fat and can be either salted or unsalted. It is used to add fat and rich flavor to recipes, often preferred over margarine or other butter substitutes.
Useful Links:
Tip: How to Soften Butter Quickly | SimplyRecipes.com
Don’t Make These Common Mistakes When Cooking (or Baking!) with Butter | Bon Appetit
Fun related videos

How to Make Lemon Butter Sauce : Butter Sauces

Why Can Applesauce Replace Butter? And Oil? And Eggs?

Butter Cake

Basic Beurre Blanc recipe from the World's Premier Culinary College

How to make Butter Croissants
How to Make Lemon Butter Sauce : Butter Sauces
Source: cookingguide
Why Can Applesauce Replace Butter? And Oil? And Eggs?
Source: SciShow
Butter Cake
Source: TheCulinarycorner
Basic Beurre Blanc recipe from the World's Premier Culinary College
Source: The Culinary Institute of America
How to make Butter Croissants
Source: TheCulinarycorner