&& and || in C# application

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace hey_there_this_is_the_latest_c_sharp_program
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Button1_Click(object sender, EventArgs e)
        {
            if (textBox1.Text == "Bishal" || checkBox1.Checked) {
                MessageBox.Show("Welcome");
            }
        }
    }
}