Difference between DataReader, Dataset, DataTable and DataAdapter in ASP.NET

DataReader:

It is read only format, we can't update records.

It is connection oriented, whenever data bind from database that need connection and then connection is disconnected.

Code Behind:

protected void Bind()
{
   SqlConnection con = new SqlConnection("Data Source=database;Integrated Security=true;Initial Catalog=catalog");
   {
      con.Open();
      SqlCommand cmd = new SqlCommand("Select record FROM table", con);
      SqlDataReader dr = cmd.ExecuteReader();
      grdvw.DataSource = dr;
      grdvw.DataBind();
      con.Close();
   }
}

Dataset:

It is connectionless oriented.

Whenever we bind data from database. It connects indirectly to the database and then disconnected. Its easily read and write data from database.

Code Behind:

protected void Bind()
{
   SqlConnection con = new SqlConnection("Data Source=datasource;Integrated Security=true;Initial Catalog=catalog");
   con.Open();
   SqlCommand cmd = new SqlCommand("select record from table", con);
   SqlDataAdapter da = new SqlDataAdapter(cmd);
   DataSet ds = new DataSet();
   da.Fill(ds);
   grdvw.DataSource = ds;
   gvdvw.DataBind();
}

DataTable:

DataTable represents a single table in the database.

It has rows and columns. There is no much difference between dataset and datatable, Dataset is simply the collection of datatables.

Code Behind:

protected void Bind()
{
   SqlConnection con = new SqlConnection("Data Source=datasource;Integrated Security=true;Initial Catalog=catalog");
con.Open();
   SqlCommand cmd = new SqlCommand("select record from table", con);
   SqlDataAdapter da = new SqlDataAdapter(cmd);
   DataTable dt = new DataTable();
   da.Fill(dt);
   grdvw.DataSource = dt;
   gvdvw.DataBind();
}

DataAdapter:

Dataadapter is a disconnected oriented architecture.

DataAdapter is like a mediator between DataSet (or) DataTable and database. This dataadapter is used to read the data from database and bind to dataset.

.cs page
protected void Bind()
{
   SqlConnection con = new SqlConnection("Data Source=datasource;Integrated Security=true;   Initial Catalog=catalog");
   con.Open();
   SqlCommand cmd = new SqlCommand("select record from table", con);
   SqlDataAdapter da = new SqlDataAdapter(cmd);
   DataSet ds = new DataSet();
   da.Fill(ds);
   grdvw.DataSource = ds;
   gvdvw.DataBind();
}