is it importatnt to write public in function code example

Example 1: public static void main(String[] args)

public static void main(String[] args)

Example 2: what does "string[] args" mean in c# main method?

class Program
{
  static void Main(string[] args)
  {
    foreach (var arg in args)
    {
      Console.WriteLine(arg);
    }
  }
}