Under Perens' definition, open source describes a broad general type of software license that makes source code available to the general public with relaxed or non-existent copyright restrictions.
1 Illnesses such as the flu or colds. Home treatment of your flu and cold symptoms usually will relieve lightheadedness. 2  Vomiting, diarrhea, fevers, and other illnesses that cause dehydration.  Very deep or rapid breathing (hyperventilation).
Tension headaches, caused by muscle tension, are marked by pain, pressure and tightness around the head. Low blood pressure (hypotension) Low blood pressure, or hypotension, can make you feel lightheaded and dizzy. Medication reaction or side-effect. Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more. Chronic kidney disease. Chronic kidney disease is a condition of the kidneys that can cause high blood pressure, fatigue, and weakness.