I keep getting these randome hives that comes, itch like crazy and then go away. What could it be?

Quick overview. Acute hives lasting <6 weeks: food or drug allergy, viral or streptococcal infections. Chronic hives >6 weeks: common: idiopathic & autoimmune; rare: parasites, malignancy, mastocytosis, food allergy. Physical urticaria: due to increased mast cell fragility: dermatographism (literally skin writing), pressure, delayed pressure, vibration, cold, hot, sunlight. If answer not obvious see an allergist.
Possibly allergy. Hives can be due to an allergy to a food. This can progress to a more serious reaction. It is also possible your hives are due to other causes and will never become more serious. Evaluation by a board certified allergist is recommended.