There were other applications proposed in the early days of the. Internet, including packet based voice communication (the. precursor of Internet telephony), various models of file and disk. sharing, and early âwormâ programs that showed the concept of. agents (and, of course, viruses). A key concept of the Internet is.
View All. For a long time, normal blood pressure was defined as 120/80 mm Hg (systolic/diastolic). Recently, however, the American Heart Association revised its guidelines about what an optimal blood pressure range is, and when blood pressure is considered too high or too low. While 120/80 used to be considered normal, the new guidelines define three levels of abnormal blood pressure values. 120-139 / 80-89 is now considered to be âprehypertensionâ (or âalmost high blood pressure), and doctors are watching blood pressures in this range more carefully than in the past.
When your heart beats, it contracts and pushes blood through the arteries to the rest of your body. This force creates pressure on the arteries. This is called systolic blood pressure. A normal systolic blood pressure is 120 or below.A systolic blood pressure of 120-139 means you have normal blood pressure that is higher than ideal, or borderline high blood pressure. Even people with this level are at a greater risk of developing heart disease. normal diastolic blood pressure number is 80 or less. A diastolic blood pressure between 80 and 89 is normal but higher than ideal. A diastolic blood pressure number of 90 or higher, on repeated measurements, is considered to be hypertension or high blood pressure.