How to add a new item to a list

using(SPSite mySite = new SPSite(http://mysite))
{
using(SPWeb myWeb = mySite.OpenWeb())
{
SPList contactsList = myWeb.Lists["Contacts"];
SPListItem mynewItem = contactsList.Items.Add();
mynewItem ["First Name"] = "Hament";
mynewItem ["Last Name"] = "Verma";
mynewItem .Update();
}
}