What is RSS, and reading and writing RSS feeds

using System;
using System.Web.UI.WebControls;
using System.Data;
using System.Xml;
using System.Text;

public partial class RSSWrite : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void btnPublish_Click(object sender, EventArgs e)
    {
        Response.Clear();
        XmlTextWriter RSSFeed = new XmlTextWriter(System.Web.Hosting.HostingEnvironment.ApplicationPhysicalPath + "AvgPriceList.xml",Encoding.UTF8);
        // Write the rss tags like title, version, Channel, title, link description copyright etc. 
        RSSFeed.WriteStartDocument();
        RSSFeed.WriteStartElement("rss");
        RSSFeed.WriteAttributeString("version", "2.0");
        RSSFeed.WriteStartElement("channel");
        RSSFeed.WriteElementString("title", "Products Above Average Prices");
        RSSFeed.WriteElementString("link", "http://localhost/RSSFeeds");
        RSSFeed.WriteElementString("description", "Details of all the Products Average Prices");
        RSSFeed.WriteElementString("copyright", "Copyright Indrajeeth 2010");

        //here I am binding grid using SQLdatasource, This is for the example purpose reading from gridview 
        //it is not recomended use gridview, datatables,dataset to write data
        // Loop through the Gridview of the database and add them to the RSS feed

        foreach (GridViewRow grvRow in grvRSS.Rows)
        {
            RSSFeed.WriteStartElement("item");
            RSSFeed.WriteElementString("ProductName", grvRow.Cells[0].Text);
            RSSFeed.WriteElementString("UnitPrice", grvRow.Cells[1].Text);
            RSSFeed.WriteElementString("Link", "http://localhost/RSSFeeds/ProductList.xml");
            RSSFeed.WriteElementString("PublishDate", DateTime.Now.ToString());
            RSSFeed.WriteEndElement();
        }
        RSSFeed.WriteEndElement();
        RSSFeed.WriteEndElement();
        RSSFeed.WriteEndDocument();
        RSSFeed.Flush();
        RSSFeed.Close();
        Response.Write("RSS Feed is created. For reading Rss feed <a href='RSSRead.aspx'>Click here.</a>");
    }
}