Cache, Session, and ViewState

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class CachePage : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            if (Cache["Name"] != null)
            {
                LblCacheVariable.Text = Cache["Name"].ToString();
            }
            else
            {
                LblCacheVariable.Text = "NULL";
            }
        }
    }
    protected void ButtonAdd_Click(object sender, EventArgs e)
    {
        Cache["Name"] = TBName.Text;
        LblCacheVariable.Text = Cache["Name"].ToString();
    }
}