Platelet count refers to the number of platelets present in a specific volume of blood. A high platelet count, known as thrombocytosis, is typically defined as having more than 450,000 platelets per microliter of blood. Thrombocytosis can be caused by various factors, including infection, inflammation, certain medications, or bone marrow disorders. On the other hand, a low platelet count, known as thrombocytopenia, is generally diagnosed when there are fewer than 150,000 platelets per microliter of blood. Thrombocytopenia can result from conditions like immune disorders, viral infections, medication side effects, or bone marrow dysfunction. It is important to consult with a healthcare professional for an accurate diagnosis and appropriate management of platelet count abnormalities.