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).
Light-headedness may also occur if you have the flu, low blood sugar, a cold, or allergies. More serious conditions that can lead to light-headedness include: 1  Heart problems, such as a heart attack or abnormal heart beat.