When TV became rectangular (my grandfather had a round one) the picture was given the same aspect ratio (width to height) as old 30's and 40's films (1:33 to 1, or just slightly wider than high.) In the fifties and sixties the film industry waged technological war against television, creating bigger and wider pictures, 2:35 to 1 for CinemaScope up to 2.75 to 1 for Cinerama, MGM Camera 65, Ultra Panavision70 and various other highfalutin film formats, before settling down to the current standard of 1.88 to 1.
When these films are shown on video, the picture has to be carved down to fit the 1:33 to 1 format of your TV screen. The sides are lopped off, and the image is slid to the left and right in a desperate and often futile attempt keep the center of the action, or whatever character is speaking, on screen. This particular form of film mutilation is called Scan and Pan. Sometimes when two characters are talking all you see are their noses, or the picture sways mechanically from left to right like a tennis match, or you can hear actors and action but can not see it on the television screen. In one scene of Gunfight at the O.K. Corral Deforest Kelly can be heard but not seen as the camera stays rock steady on Burt Lancaster and Kirk Douglas (this was before Star Trek).
When Laser Discs finally became marginally popular, the increased picture clarity, coupled with the fact that Laser Disc buyers rarely own 10 inch TVs, and desperately needed some excuse for paying twice as much for films, made Letterboxing practical. Letterboxing has long been used during opening and closing titles (since titles tend to fill the screen, and loping them off on either side would make them unintelligible). Black bands appear on the top and bottom of the screen and the film is sandwiched between them. When the entire film is shown this way, the original aspect ratio is maintained, nothing is cut off from the sides, and the complete picture as you would see it in a theater (if you had trouble parking, and could only get a seat in back). If you've got a reasonably large TV screen, or sit a little closer (remember they're no gain without eye strain), this is a much superior way to watch a good movie. When foreign films are shown this way subtitles can be moved to the black band below the picture where they're much easier to read and don't get in the way of the cinematography, Janus is doing this to its large collection of Japanese and French films.
Now Bravo, American Movie Classics, Turner, and occasionally The Movie Channel and PBS frequently show Letterboxed films. Several times a week AMC will show a "Scan and Pan" version in the early evening that is rerun in Letterbox format late at night, when it won't frighten the children. They have a large library of classic films in this format including John Wayne's first starring role The Big Trail (1930) shot in an early widescreen format called Grandeur & the restored version of Spartacus complete with original trailer, newsreel footage of the London opening, the Overture and Intermission music, and Lawrence Olivier's shellfish speech. TNT frequently shows Forbidden Planet, Jailhouse Rock and Paint Your Wagon. Turner has also been showing musicals with the lyrics printed below the picture, so everyone can sing along with Clint Eastwood and Lee Marvin. PBS has 2001: A Space Odyssey (mainly during pledge things) and occasional British and European TV productions such as Sharpe's Rifles. Many European TV productions are now being shot in widescreen format in anticipation of high definition TV (check out the Learning Channel). Babylon 5 will be released this summer in Letterboxed format (at least for the laser disc release).
Currently available on Video Tape are such titles as Jurassic Park, Spartacus (restored version), Ben Hur (in a special edition), the Star Trek movies (although this may just be available in one of the boxed sets, i.e., you have to buy 1, 3 and 5 too), It's a Mad, Mad, Mad, Mad World (restored to its original 3 hour Cinerama run time), Blade Runner (the director's cut), and Manhattan (cause Woody wanted it that way). Check the box carefully! Letterboxing is still the exception rather than the rule, and sold side by side with the Scan & Pan versions. Letterbox versions are often sold as "Special Collectors Editions" or will have Widescreen or Letterboxed version printed on it. Beginning last fall, Scan & Pan versions are required to say "Reformatted to fit your TV Screen" on the video box and when they are shown on Network TV.
Please buy or rent these versions whenever you find them. The people who market video tape are afraid that the public is not ready to cope with blank space on the top and bottom of the screen, although someday some marketing type at the networks is going to see the inherent advertising potential here (Hell it worked for the World Cup).