I love John Carpenter's films and The Fog is certainly no exception. It's a film that does a lot with very little and I mean that as a sincere compliment. Carpenter starts with a interesting screenplay that doesn't lay all of its cards on the table at the beginning of the film. Then he loads his cast with great, emotive actors such as Adrienne Barbeau [Swamp Thing, Creepshow], Jamie Lee Curtis [Halloween, True Lies], Janet Leigh [Psycho, Touch of Evil], and Hal Holbrook [Creepshow, All the President's Men] who make us care what is happening on screen.
Finally, he brings in just the right amount of special effects: a creepy day-glo fog, a weird pulsing soundtrack [Carpenter wrote the score like he did with Halloween], an arm of the living dead here, a knock at the door there. It all adds up to an old-fashioned fright where less is more. Your mind fills in all the gory details including the blood splatter which we actually see very little of on screen. Nicely done!
A remake of The Fog was done in 2005 but it's not as good as the original. The sequel's strong suit is that it fleshes out the backstory a bit more than the original film does and I love the ghost effects in it as well. As far as I'm concerned you can't go wrong with either version. [The sequel is much better than critics say it is.] Watch them both for yourself and let me know which one you prefer.
For more info check out the film's entry in IMDB.