When planning out my programs, I often start with a chain of thought like so:
A football team is just a list of football players. Therefore, I should represent it with:
var football_team = new List<FootballPlayer>();
The ordering of this list represent the order in which the players are listed in the roster.
But I realize later that teams also have other properties, besides the mere list of players, that must be recorded. For example, the running total of scores this season, the current budget, the uniform colors, a string representing the name of the team, etc..
So then I think:
Okay, a football team is just like a list of players, but additionally, it has a name (a string) and a running total of scores (an int). .NET does not provide a class for storing football teams, so I will make my own class. The most similar and relevant existing structure is List<FootballPlayer>, so I will inherit from it:
class FootballTeam : List<FootballPlayer>
public string TeamName;
public int RunningTotal