The Tokay Gecko is common in Thailand and will even sometimes be found in the home.  Many people unnecessarily fear this gecko but it is not poisonous or especially dangerous.  Tokays are aggressive however, and will bite -- so it's best not to handle them with your bare hands.

Most people appreciate these geckos because they eat pests such as scorpions and centipedes.  Like all species, they are an important part of their ecosystem.
 

If it is threatened, the Tokay will open it's mouth wide and hiss.  If you are careless and get a finger too close to its mouth the Tokay will bite. The Tokay often won't let go once it has clamped down for several minutes or even up to an hour.  To encourage the gecko to let go, just put a drop of vinegar on it's nose; this usually works.

If you find one in your home, use a small shovel or long handled dust pan to take the gecko outside.
 

The Tokay in the photo above is missing its tail.  If a gecko is attacked by a predator (in this case probably a dog or bird), the tail can snap off and will wriggle, distracting the predator while the gecko can escape.  The tail will later grow back.

The Tokay Gecko is the second largest gecko species and can grow to about 30-40 cm long, weighing around 325 grams for males and 20-30 cm and about 250 grams for females.

They range in color from blue or gray with spots which can be yellow to bright red.  Males are generally more brightly colored than the females.  Tokays have the ability to lighten or darken their skin slightly in order to better blend with their environment.
 

Tokays have a loud call and the sounds they make vary from clicking, chirping and are sometimes described as sounding like "to-ken" or "to-kay", or "geh-ko", which is where the animal gets it's name.  Click the video below to see and hear a Tokay calling: 

Tokays are solitary and meet only during the mating season.  The females lay clutches of one or two hard shelled eggs, which they guard until they hatch.

The males are very territorial and will attack other males they see as usurpers.

These geckos are generally noctural and rarely seen during the day.

Tokays live from 7 to 10 years in the wild and have been known to live up to 18 years in captivity.

Some people keep Tokays as pets, but because they like to bite, this is only recommended for experienced reptile keepers. 

One thing newcomers to Thailand may be surprised to find in their homes is the house lizard.  If you are from a northern country, you obviously are not used to having reptiles in your home, unless you fancy them as pets.

Maybe these cute little creatures should be considered pets, even though they come completely free of charge and delivered by mother nature.  They are beneficial because they eat mosquitoes and other pesky insects that are all so common here.  People like the house lizards because of this handy feature.

You may have to clean up their droppings from time to time, but that is the only price you pay for their service.

The house lizard is commonly called a "jing-jok" (Thai: จิ้งจก) after the chirping sound they often make.

House lizards store fat in their tails for times when insects are scarce (whenever would THAT be?).  Their tails also detach when a cat or larger lizard tries to capture them.  The tail grows back afterwards.