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).
Lightheadedness has many causes, including: 1  Allergies. 2  Illnesses such as the flu or colds. 3  Home treatment of your flu and cold symptoms usually will relieve lightheadedness. 4  Vomiting, diarrhea, fevers, and other illnesses that cause dehydration.5  Very deep or rapid breathing (hyperventilation).hen this happens, lightheadedness and fatigue may be the first noticeable symptoms that you are losing blood. Heavy menstrual bleeding also can cause this type of lightheadedness. Sometimes the cause of lightheadedness is an abnormal heart rhythm (arrhythmia), which can cause fainting spells (syncope).