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).
Medication reaction or side-effect Medication side effects include nausea, vomiting, stomach upset, weakness, dizziness, seizures, and more. Fainting (vasovagal syncope) Before fainting, you might feel lightheaded, warm, nausea, a cold sweat, or have tunnel vision. Heart rhythm disorder Some heart rhythm disorders can cause a fluttering in the chest, shortness of breath, chest pain or dizziness.