In easy terms, throw a ball into the air so it will land away from you, this is the path taken by a ballastic missile, now throw the ball using an under arm bowl so it travels paralell to the ground until it loses momentum and falls to the ground, this is how a cruise missile travels.
A good search engine is
http://www.google.com Just enter your search word and it will usually give you some good related answers.
"A
ballistic missile is a
missile, usually with no wings or fins, with a prescribed course that cannot be altered after the missile has burned its fuel, whereafter its course is governed by the laws of
ballistics. In order to cover large distances ballistic missiles must be launched very high into the air or in space, in a
sub-orbital spaceflight; for intercontinental missiles the altitude halfway is ca. 1200 km. When in space and no more
thrust is provided, the missiles are
freefalling."
"A
cruise missile is a guided
missile which uses a lifting wing and most often a
jet propulsion system to allow sustained flight. Cruise missiles are, in essence, unmanned
aircraft. They are generally designed to carry a large conventional or
nuclear warhead many hundreds of miles with excellent accuracy. In
2001, modern cruise missiles normally travel at sub-sonic speeds, are self-navigating, and fly low in order to avoid
radar detection."
Bothof these answers came form a google search leading to a online encyclopedia site. This is it
http://en.wikipedia.org/wiki/Main_Page
Hope this helps
