What is the type of fluid found in the human brain ?

Within the cerebral hemisphere of a brain there lies a cavity called ventricles. They contain a nutritive fluid which is called the cerebrospinal fluid. 

Cerebrospinal fluid (CSF) is a clear, colorless body fluid  that is found in the brain and spinal cord of the human body. It is produced by specialized ependymal cells in the choroid plexuses of the ventricles of the brain, and absorbed in the arachnoid granulations. Cerebrospinal fluid is the liquid around your brain and spinal cord that If a doctor thinks you have an illness that affects your nervous system, they might take a sample for testing. If you have any micro organism or organism in the brain or the nervous system like meningitis than the CSF changes color and is non transparent.