I need help understanding Methods

class Program
{
    static void Main(string[] args)
    {
        string Party = AnnounceParty("Beach", 5, "Shaq", "Jackson", "Jake", "Philip");
        Console.WriteLine(Party);

    }
    static string AnnounceParty(string location, int hours, params string[] guests)
    {
        string guestList = "";
        foreach (string guest in guests)
        {
            guestList += guest + ",";
        }
        return $"The party is at {location} at {hours}PM. Guests: {guestList}";
    }
}