What Causes Dizziness?

Sir, I am 58 years old and quite healthy without any major health problems like bp,sugar etc.today since morning I feel little bit of reeling my head occasionally.it is repeating no of times since morning today.i did not feel any uncomfort but I find it new to me.i fear it may lead to further health problems. pl advice any medices to be used or any precautionsto be taken. so that I will take necessary steps. thank u sir k satyanarayana from Visakhapatnam a.p. india