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.
Normal blood pressure is a systolic pressure of less than 120 and a diastolic pressure of less than 80. Systolic pressure (the upper number in a blood pressure reading) refers to pressure in the arteries when the heart beats.ormal blood pressure is a systolic pressure of less than 120 and a diastolic pressure of less than 80. Systolic pressure (the upper number in a blood pressure reading) refers to pressure in the arteries when the heart beats.