n special effects, especially considering the cutting-edge technology we have today that can make even the most bizarre scenes seem realistic, such as alien life forms, spectacular battles in outer space, time travel or traveling to other worlds at the speed of light, and the like.

Its hard to define precisely what makes a science fiction film because the genre has no universally accepted definition. In fact, science fiction may vary from viewer to viewer in that what is sci-fi to me may be fantasy or horror to you. One thing though is that science fiction films are purely speculative in nature and are peppered with recurring themes involving science and technology. Other prevalent themes in sci-fi movies are mysticism, magic, the occult and the supernatural, which are also key elements of fantasy or occult/religious movies. In fact, quite a number of films blur the line between these genre, such as Forbidden Planet, Chronicles of Riddick, and the Star Wars series.

Through the years, the special effects in science fiction movies have ranged from the downright horrible and laughable to those that are awe-inspiring and breath-taking. Some of the great milestones in this regard are marked by films such as 2001: A Space Odyssey, the Star Wars films, Star Trek: The Motion Picture and The Matrix.

These days, if youve missed any of the great sci-fi movies, you can always catch them on DVD, which has a wide array of selections dating back to the early days of science fiction. Theres nothing like going on a sci-fi binge and watching movie after movie on DVD.

Science fiction DVDs are readily available in superstores like Best Buy, Wal-Mart and Target as well as in your local DVD shop. Keep your eyes open for a bargain or two. You may even want to order your DVDs online at sites like Amazon.com or Ebay for greater convenience.