How To Read Margin

So, you got or code like this:  margin:10px 20px 30px;, or this: margin:10px 20px 30px 40px;.
Can you read it? If not, well, here is the explanation:
1. margin:10px 20px 30px;
meaning:
Top is 10px
Left and right are 20px
Bottom is 30px

2. margin:10px 20px 30px 40px;
meaning:
Top is 10px
Right is 20px
Bottom is 30px
Left is 40px