Security C#

using System;
using System.Text;
using System.Security.Cryptography;
class MainClass {
    public static void Main(string[] args) {
        HashAlgorithm hashAlg = null;
        hashAlg = new SHA1Managed();
        using (hashAlg) {
            byte[] pwordData = Encoding.Default.GetBytes(args[1]);
            byte[] hash = hashAlg.ComputeHash(pwordData);
            Console.WriteLine(BitConverter.ToString(hash));
        }
    }
}