There are many different types of intellectual disability, each with its own unique characteristics and causes. Some common types of intellectual disability include:

Down syndrome: This is the most common chromosomal disorder, caused by the presence of an extra copy of the 21st chromosome. It is characterized by intellectual and developmental delays, as well as physical abnormalities such as a flat facial profile and short stature.

Fragile X syndrome: This is the most common inherited form of intellectual disability, caused by a mutation in the FMR1 gene. It is characterized by intellectual and developmental delays, as well as physical and behavioral characteristics such as a long face, large ears, and anxiety or attention deficit disorders.

Rett syndrome: This is a rare genetic disorder that primarily affects girls and is caused by mutations in the MECP2 gene. It is characterized by intellectual and developmental delays, as well as physical and behavioral symptoms such as slowed head growth, hand wringing, and lack of speech.

Phenylketonuria (PKU): This is an inherited disorder caused by a deficiency of the enzyme phenylalanine hydroxylase, which is necessary for the metabolism of the amino acid phenylalanine. It is characterized by intellectual and developmental delays, as well as physical symptoms such as fair skin, light hair, and a musty odor in the breath and urine.

Intellectual disability due to prenatal alcohol exposure: This type of intellectual disability is caused by a mother's alcohol use during pregnancy, which can interfere with fetal brain development. It is characterized by intellectual and developmental delays, as well as physical and behavioral symptoms such as low birth weight, small head size, and hyperactivity or attention deficit disorders.

It's important to note that these are just a few examples of the many different types of intellectual disability, and that each individual with the condition may experience a unique combination of symptoms and challenges.