This document discusses the history and characteristics of non-governmental organizations (NGOs). It outlines how NGOs evolved from the 1950s focusing on charity work to the 1990s when they started focusing on sustainable development. The key characteristics of NGOs are that they are private institutions working for public benefit, do not need to be registered, are self-governing, not-for-profit, and operate on a voluntary basis. Understanding the fundamental characteristics of NGOs is essential to comprehending the concept.