Why use this.... <%# Eval("") %>'

Question

What is the use of <%# Eval("") %>. I am not able to understand what is the purpose ot this thing.<asp:DataList ID="DataList1" runat="server" DataSourceID="XmlDataSource1">
<ItemTemplate>
name:
<asp:Label ID="nameLabel" runat="server" Text='<%# Eval("name") %>' />
<br />
id:
<asp:Label ID="idLabel" runat="server" Text='<%# Eval("id") %>' />
<<br />br />
</ItemTemplate>
</asp:DataList>