Lichtenberg was the youngest of seventeen children of pastor Johann Conrad Lichtenberg. His father, ascending through the ranks of the church hierarchy, eventually became superintendent for Darmstadt. Unusually for a clergyman in those times, he seems to have possessed a fair amount of scientific knowledge. Georg Christoph Lichtenberg was educated at his parents' house until ten years of age, when he joined the Lateinschule in Darmstadt. His intelligence and wit became obvious at a very early age. He wanted to study mathematics, but his family could not afford to pay for lessons. In 1762 his mother applied to Ludwig VIII, Landgrave of Hesse - Darmstadt, who granted sufficient funds. In 1763, Lichtenberg entered Göttingen University, where in 1769 he became extraordinary professor of physics, and six years later ordinary professor. He held this post till his death.

Lichtenberg became a hunchback owing to a malformation of the spine. This left him unusually short, even by eighteenth century standards. Over time this malformation grew worse, ultimately affecting even his breathing.

One of the first scientists to introduce experiments with apparatus in their lectures, Lichtenberg was a most popular and respected figure in the European intellectual circles of his time. He maintained good relations with most of the great figures of that era, including Goethe and Kant. In 1784 Alessandro Volta visited Göttingen especially to see the man and his experiments. The eminent mathematician Karl Friedrich Gauss was one of the hearers of his lectures. In 1793 he was elected a member of the Royal Society.

As a physicist, today he is remembered for his investigations in electricity, for discovering branching discharge patterns on dielectrics now called Lichtenberg figures. In 1777, he built a large electrophorus in order to generate static electricity through induction. One of the largest ever made, it was 6 feet (2 m) in diameter and could produce 15 inch (38 cm) sparks. With it, he discovered the basic principle of modern Xerography copy machine technology. By discharging a high voltage point near an insulator, he was able to record strange tree like patterns in fixed dust. These Lichtenberg figures are considered today to be examples of fractals.

He was one of the first to introduce Benjamin Franklin's lightning rod to Germany by installing such devices to his house in Göttingen and his garden sheds. He also proposed the standardized paper size system used all over the world today (except in the US and Canada), known as ISO 216, which has A4 as the most commonly used size.

Invited by his students, he visited England twice, from Easter to early summer 1770 and from August 1774 to Christmas 1775, where he was received cordially by George III and Queen Charlotte. He led the King through the royal observatory in Richmond, upon which the king proposed that he become professor of philosophy. He also met with participants of Cook's voyages. Great Britain impressed him, and he became a well known Anglophile after the visits.

He had many romances. Most of the women were from poor families. In 1777 he met Maria Stechard, then aged 13, who lived with the professor permanently after 1780. She died in 1782. In the following year he met Margarethe Kellner (1768 – 1848). He married her in 1789, in order to give her a pension, as he thought he was to die soon. She gave him six children, and outlived him by 49 years.

Lichtenberg was prone to procrastination. He failed to launch the first ever hydrogen balloon, and although he always dreamed of writing a novel à la Fielding's Tom Jones, he never finished more than a few pages. He died at the age of 56, after a short illness.

The "waste books" (Sudelbücher in German) are the notebooks he kept from his student days until the end of his life. Each volume was accorded a letter of the alphabet from A, which begun in 1765, to L, which broke off at Lichtenberg's death in 1799.

These notebooks first became known to the world after the man's death, when the first and second editions of Lichtenbergs Vermischte Schriften (1800 - 06 and 1844 - 53) were published by his sons and brothers. Since the initial publications, however, notebooks G and H, and most of notebook K, were destroyed or disappeared. Those missing parts are believed to contain sensitive materials. The manuscripts of the remaining notebooks are now preserved in Göttingen University.

The notebooks contain quotations that struck Lichtenberg, titles of books to read, autobiographical sketches, and short or long reflections. It is those reflections that help Lichtenberg earn his posthumous fame. Today he is regarded as one of the best aphorists in the Western intellectual history.

Some scholars have attempted to distil a system of thought out of Lichtenberg's scattered musings. However, Lichtenberg was not a professional philosopher, and had no need to present, or to have, any consistent philosophy.

The waste books nevertheless reveal a critical and analytical way of thinking and emphasize on experimental evidence in physics, through which he became one of the early founders and advocates of modern scientific methodology.

The more experience and experiments are accumulated during the exploration of nature, the more faltering its theories become. It is always good though not to abandon them instantly. For every hypothesis which used to be good at least serves the purpose of duly summarizing and keeping all phenomena until its own time. One should lay down the conflicting experience separately, until it has accumulated sufficiently to justify the efforts necessary to edifice a new theory. (Lichtenberg: waste book JII/1602)

The reflections also include keen observations on human nature, à la the 17th century French moralists.

Schopenhauer admired Lichtenberg for what he had written in his notebooks greatly. He called Lichtenberg one of those who "think ... for their own instruction", who are "genuine thinkers for themselves in both senses of the words". Other admirers of Lichtenberg's notebooks include Nietzsche, Freud and Wittgenstein. Lichtenberg is not read by many outside Germany. Leo Tolstoy held Lichtenberg's writings in high esteem, expressing his perplexity of "why the Germans of the present day neglect this writer so much." The Chinese scholar and wit Qian Zhongshu quotes the Waste books in his works several times. A crater on the Moon is named Lichtenberg in his honour.

As a satirist, Lichtenberg takes high rank among the German writers of the 18th century. His biting wit involved him in many controversies with well known contemporaries, such as the Swiss physiognomist Johann Kaspar Lavater whose science of physiognomy he ridiculed, and Johann Heinrich Voss, whose views on Greek pronunciation called forth a powerful satire, Über die Pronunciation der Schöpse des alten Griechenlandes. For Laurence Sterne's wit on the bigotry of the clergy, in his novel Tristram Shandy, Lichtenberg condemned him as a scandalum ecclesiae (a scandal for the Church).

In 1777, Lichtenberg opposed the apparent misrepresentation of science by Jacob Philadelphia. Lichtenberg considered him to be a magician, not a physicist, and created a satirical poster that was intended to prevent Philadelphia from performing his exhibition in Göttingen. The placard, called "Lichtenberg's Avertissement", described extravagant and miraculous tricks that were to be performed. As a result, Philadelphia left the city without a performance.

In 1784 he took over the publication of the textbook Anfangsgründe der Naturlehre ("Foundations of the Natural Sciences") from his friend and colleague Johann Christian Erxleben upon his premature death in 1777. Until 1794, three further editions had followed. For many years, the Anfangsgründe remained the standard textbook for physics in German.

He published the Göttinger Taschencalender from 1778 onwards, and contributed to the Göttingisches Magazin der Wissenschaften und Literatur, which he edited for three years (1780 – 1782) with J.G.A. Forster. The Göttinger Taschencalendar, beside being a usual Calendar for everyday usage, contained not only short writings on natural phenomena and new scientific discoveries (which would be termed popular science today), but also essays in which he contests quackery and superstition. It also contained attacks on the “Sturm und Drang” writers. In the spirit of enlightenment, he strived to educate the common people to use logic, wit and the power of their own senses.

Based on his visits to England, his Briefe aus England, with admirable descriptions of Garrick's acting, are the most attractive of his writings published during his lifetime. He also published from 1794 to 1799 an Ausführliche Erklärung der Hogarthischen Kupferstiche, in which he described the satirical details in William Hogarth's prints.

Freud (in his "Why War?" letter to Einstein) mentions Lichtenberg's invention of a "Compass of Motives" in a discussion on the combination of human compounded motives and quotes him as saying, "The motives that lead us to do anything might be arranged like the thirty - two winds and might be given names on the same pattern: for instance, 'food-food-fame' or 'fame-fame-food'."