How MySQL myisam table is stored on disk?

I am learning MySQL storage engines. I need some help about MySQL MyISAM storage engine. Can you help me to explain, how MySQL MyISAM table is stored on disk?

MySQL stores each MyISAM table on disk in three files. The files have names that begin with the table name and have an extension to indicate the file type.

1. An .frm file stores the information about table format.
2. The file containing table data has an .MYD (MYData) extension.
3. The file containing information about table indexes has an .MYI (MYIndex) extension.