The Krusty Krab is a resturant owned by Mr. Krabs. The Krusty Krab deals mainly in selling Krabby Patties, normally accompanied by fries. It's current employees consist of SpongeBob SquarePants as fry cook and Squidward Tentacles as cashier.
The Krusty Krab is a very famous as well. While selling Krabby Patties, which are so delicious that Plankton tries to steal the secret formula, Mr. Krabs is counting the money he made from the Krabby Patties. Mr. Krabs' cheap nature has also caused him to set rules such as 'No free refills' and 'No free napkins' in order to obtain more cash. At one point, he charged his employees for existing, breathing, lollygagging, etc. The Krabby Patties have a secret recipe, which makes them so delicious, that makes it a popular hangout spot in Bikini Bottom. The Krusty Krab has a major rival though, The Chum Bucket. The Chum Bucket is owned by Plankton and his computer wife Karen. However, the Chum Bucket has almost no business, and even though Plankton has tried to steal the secret Krabby Patty Recipe many times, he has never succeeded permanently. He does manage to steal the formula in The SpongeBob SquarePants Movie, though SpongeBob saves the day and Mr. Krabs from a fiery death at the hands of King Neptune.
In The SpongeBob SquarePants Movie, there was a Krusty Krab 2, located right next to the original one. Though there is no sign of it being closed, the KK2 never appeared in another episode.
The Krusty Krab is also known for strange facilities. In one episode, SpongeBob uses a furnace located in the corner to cremate a Krabby Patty that was only half eaten. This shows that it's not just the customers they treat well, but the food too.
 Kuddly Krab
Once, The Krusty Krab got changed to the Kuddly Krab because Mr. Krabs let his daughter Pearl run the place. It was turned into a spot for teens to hang out and relax. Problem is all that is served here was "Salad"...
 Krabby O' Mondays
In the episode Selling Out The Krusty Krub was changed into Krabby O' Mondays. The workers still remained the same for both of these, but Mr. Krabs had retired. He later returned as a dish washer.
 Rusty Krab
In the episode Krusty Krab Training Video, the Krusty Krab is revealed to have once been a retirement home that Mr. Krabs had obtained. The only aesthetic changes seen in the show is that the 'Krusty Krab' sign lacks the 'K' in 'Krusty'.
 Krusty Kantina
Appearing in the episode Pest of the West, The Krusty Kantina is a restaurant owned by Mr. Krabs' ancestor from Dead Eye Gulch (which was what Bikini Bottom was called at the time). The Krusty Kantina's interior consist of a bar (that only serves milk), a stage, which is used by Mrs. Puff's ancestor, and a piano, which can be played manually, or can be played automatically by inserting a coin in it's coin slot.
 Krusty Sponge
The Krusty Sponge is the aesthetically redesigned version of the Krusty Krab appearing in the episode The Krusty Sponge. After receiving a good review from a highly accredited food critic (Gene Scallop), Spongebob became a celebrity in bikini bottom. In an effort to attract customers, Mr. Krabs redisigned his resataurant with a Sponge theme. Items such as straws, napkins, ice cubes and Krabby Patties (which were really mouldy Krabby Patties) were used in the restaurant. It also had a Spongebob themed train ride running outside the restaurant. However, the mouldy patties later
 Krusty Towers
Krusty Towers replaced the Krusty Krab in the episode Krusty Towers. After Mr. Krabs had stayed at a hotel and seen how expensive the bill was, he was inspired to create a hotel. It consisted of 11 floors, the last being the original Krusty Krab building. It's motto, "We shall never deny a guest, even the most ridiculous request', had employees (Squidward, Spongebob, and later, Mr. Krabs) pulling off ridiculous feats, which later caused Squidward to resign. The hotel received a small amount of customers, due to the inability to obtain a Krabby Patty through normal means. Customers had to rent a room and order room service to get a Krabby Patty.
Related ThreadsHow to defeat robot in Krusty Krab to meet Santa? - last post @ Mar 31, 2010
where do you find the key to the krusty krab? - last post @ Oct 10, 2009
Krusty Krab - last post @ Dec 30, 2002
mr krabs lucky coin - last post @ Jan 20, 2010
Krabs Key - last post by @ Dec 4, 2009