Explain the following code

public int Validate_login(string Username, string Password)
    {
        SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["connect"]);
        SqlCommand cmdselect = new SqlCommand();
        cmdselect.CommandType = CommandType.StoredProcedure;
        cmdselect.CommandText = "Login_detail1";
        cmdselect.Parameters.Add("@Username", Username);
        cmdselect.Parameters.Add("@Password", Password);
        cmdselect.Parameters.Add("@OutRes", SqlDbType.Int, 4);
        cmdselect.Parameters["@OutRes"].Direction = ParameterDirection.Output;
        cmdselect.Connection = con;
        int Results = 0;
        try
        {
            con.Open();
            cmdselect.ExecuteNonQuery();
            Results = (int)cmdselect.Parameters["@OutRes"].Value;
        }
        catch (SqlException ex)
        {
            lblresult.Text = ex.Message;
        }
        finally
        {
            cmdselect.Dispose();
            if (con != null)
            {
                con.Close();
            }
        }
        return Results;
    }