Dictionary allows you to use a key to access a member of the collection.
Think: Webster’s dictionary… the word (key) then the definition (instance of a given type)
Key is anything that is meaningful in your system.
Key must be unique.
TKEY => type of the key
TValue => type of the value
Dictionary cars = new Dictionary(); cars.Add("V123", new Car{Make="BMW", Model="528i", Year=2010}); cars.Add("V132", new Car{Make="BMW", Model="575", Year=2015}); cars.Add("V321", new Car{Make="BMW", Model="533i", Year=2012}); cars.ElementAt(2).Key // returns V132 cars.Element.(2).Value // Return the Car object in the second position //Better way to access Dictionary Car v2; if(cars.TryGetValue("V132", out v2){ result += v2.Year; } //Remove if(cars.Remove("V132")){ result += "Successfully removed car"; }