Which guinea pig is right for you?
Before you decide to get a guinea pig, you should have in mind a type of breed you would prefer. Also, guinea pigs are very social animals, so I would strongly consider getting at least two. More on that later. Currently, there are 13 known breeds of guinea pigs.
Here is a list of all the different breeds:
Abyssinian/Abyssinian Satin-
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Abyssinian guinea pigs have deep, tall rosettes all over the body (in case you did not know, rosettes are whirls of fur that grow evenly from a certain point on the animals coat, making it look tufted and fluffy). You may think these rosettes are random and each guinea pig is unique, but in reality each Abyssinian has eight to ten rosettes. They come in a wide variety of colors.
American/American Satin-
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Great breed for those just starting out with guinea pigs! The American breed is a smooth, short haired cavy and requires very little grooming. It is probably the most popular choice of all guinea pig breeds. It has been reported to be the calmest as well. They come in a variety of colors and beautiful shiny coat.
Coronet-
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Crested guinea pigs+Silkie guinea pigs= Coronet guinea pigs! The charming Coronet breed has a beautiful crest in addition to a flowing, long coat. While this crest looks very nice, it is important that you check under the hair over the eyes to make sure the guinea pig's eyes are still clear and bright.
Peruvian/Peruvian Satin-
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The Peruvian has the longest hair of all the breeds! It is a silky, long haired guinea pig discovered in the late 1800s. All Peruvians have two rosettes on the rump. This lively guinea pigs are known for their bright personality and are the second most (beside American guinea pigs) popular breed. They are not recommended for a first time owner because they do happen to need a lot of grooming to keep their coats knot free. You can tell the guinea pig in the picture has been very groomed. His fur is cut short enough so that he won't accidentally step on it and it is away from his eyes.
Silkie/Silkie Satin (aka Shelties)-
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Silkies are very similar to Peruvian guinea pigs, but in some ways they are very different. Their fur grows about 1 inch (2.2 cm.) every month, which is very fast. The Silkie has very short facial hair, a blunt nose and a mane that sweeps along the back with parting. Unlike their cousins, Coronets, they do not have rosettes. Currently, Silkies come in solid, self, marked, broken, white, agouti, tortoiseshell, and Himalayan.
Teddy/Teddy Satin- 
The Teddy has a frizzy, fuzzy coat. It doesn't require a whole lot of grooming. Some guinea pigs that are not the Teddy breed still carry the recessive gene, so they may produce Teddy offspring. This is never a guarantee, however. Sometimes they are incorrectly called a Rex. They are two separate breeds with different DNA. Personality wise, Teddies are very cuddly and have a good nature. They are as sweet and gentle as the look!
Texel-
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The Texel marks the third most popular guinea pig breed! It requires a lot of grooming to maintain its coat. You must also have a sort of sense for grooming artistry. The Texel has long, silky ringlets that can be easily damaged by a brush or comb, so it must be groomed by hand. Texels, by and large, are quiet, laid-back animals but are very sweet.
White-Crested-
The beautiful white crest of the American white crested! It is the fifth most popular breed, and it has one white crest on its forehead. This is the only spot where it should have white on its body. The only thing that distinguishes it from the American breed is the crest, and it is what makes them unique! I have only met a few crested guinea pigs in my life, and all have been very shy. Noodles, my own crested guinea pig, is very shy himself. He is, however, incredibly sweet and will stand on his hind legs for treats. White crests love cuddling and don't squeak very much. They very much like hidey houses and hate loud noises.
Other breeds:
Hairless "Skinny pigs" Breed-
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The hairless guinea pig, or "skinny pig" have a few short hairs on their body. For the most part they are pretty naked. Make sure your hairless doesn't catch a cold! They may be at higher risk.
More "other" breeds:
English- The English guinea pig has short, straight hair. It is less than 2 inches (3.8 cm). Despite their popularity, English guinea pigs are, inbred or outbred, used in research labs. The good news is the majority are in loving homes.
Merino- This breed is a crested Texel. The hair is longer on the rump than anywhere else.
Alpaca- The Alpaca is also known as the Merino Peruvian. It is a cross between Peruvians and Texels. They have curly fur with a dense coat all over.
Lunkarya- This breed is still being developed, but some breeders are working on perfecting the curly coat. It is a cross of Teddies and Peruvian genetics.
What type of piggie do you have?