At the time I went to school, almost every child knew the "Robinson Crusoe" by Daniel Defoe (approx. 1660-1731). There were several editions of the book, including simplified versions for children, and “Robinson” became a synonym for a hermit on a lonely island.
The bestseller found imitators, and the “robinsonades” - adventure stories about sailing ships, shipwrecked people and lonely islands - became a genre of their own. The English naval officer Frederick Marryat (1792-1848) as an example, even had a whole family stranded on a lonely island in his “Sigismund Rüstig”, where they had to fight their way through and even defend themselves against bloodthirsty natives.
Defoe's "Robinson Crusoe", however, was not a pure fantasy figure, but had a real model:
Alexander Selkirk (1676-1721)
The native Scot was a somewhat wild, experienced sailor who z. B. served as sailing master  on a number of ships, including privateers.
In October 1704, his ship landed on the "Isla Mas a Tierra" (in today's Juan Fernandez Archipelago, west of Chile in the Pacific) to look for drinking water. Not an undiscovered, but beautiful island with sufficient supplies for a number of residents and plenty of water. The climate is balanced all year round. Today around 600 people live there, mainly lobster fishermen.
After the landing, it was found that the hull was badly damaged by drilling mussels . In Selkirk's opinion, the ship could no longer reach the nearest port. The captain disagreed with Selkirk, known as the hothead, and a dispute ensued, which ended with Selkirk being left alone on the island.
That probably saved his life. Because the ship was actually so badly damaged that it capsized soon afterwards and most of the crew drowned.
Selkirk's modest equipment consisted of a musket with ammunition, flint, some tobacco, spare clothing, an ax, a saucepan and a Bible. In addition, there was a knife that every sailor carried with him.
First he camped on the beach, probably in a cave. Later he found a beautiful spring where he could build a hut. Rats brought in by a ship caused trouble, and they harassed him until he succeeded in taming cats that had also landed, which could then protect him.
He was very clever at using the island's resources:
* On the beach there were shellfish, but also large, not harmless sea lions. He was able to catch lobsters and fish in a lagoon.
* Fortunately, goats were found in the interior of the island, providing meat, milk and skins. At that time, some captains released some goats on lonely islands. As emergency provisions for shipwrecked people or as welcome additional food for ships ashore. Without natural enemies, these goats usually got along well and reproduced.
* Selkirk also knew a lot about plants: he found wild parsnips with carrot-like roots, which provided vegetables, as well as radishes, herbs and pepper berries to supplement his meat diet. The only thing he missed a lot was salt. Due to his varied diet, he remained healthier than many sailors of the time, who often suffered from scurvy.
* When his clothes were totally worn out, he had to make do with clothes he made himself from goatskins. He was able to pierce holes in the skins with a compass (a typical tool for a sailing master), which was later found by archaeologists. The twine had to be replaced by goat sinew. He did not know how to make shoes after his own were completely worn out. But his feet were now so covered with calluses that he could do without shoes.
* He even managed to forge a knife from the tires of a barrel found on the beach. To do this, he first had to produce charcoal for a sufficient forge fire. He was a versatile craftsman.
Selkirk was busy with his self-sufficiency, but loneliness weighed on him. In order not to get depressed, he read the Bible a lot. It not only tells of a jealous god of vengeance, who severely punishes any wrongdoing, but also contains - especially in the New Testament - words of hope that can give inner strength in emergencies.
When a Spanish ship landed in 1707, Selkirk had to flee into the interior of the island and hide. The Spaniards, who did not tolerate foreigners in their territory, treated him as a privateer and carried out a brief but brutal trial.
The rescue then brought the British privateer Duke on February 2, 1709, which anchored off the island and took up Selkirk. He joined the crew, whose ship, protected by a letter of piracy , fought and robbed England's enemies in the name of the Crown.
The former islander then returned to England for some time as a celebrity with some fortune in 1711.
Then he went back to sea, where he died as a lieutenant on board a British warship.
His island adventure was first made widely known in 1712 in the book "Cruising Voyage" by Woods Rogers. Recently archaeologists have been looking for traces of his stay on his island, which has since been renamed "Alejandro Selkirk" in honor of him.
 The sailing master was an experienced sailor who was responsible for navigation. Like the helmsman today.
 The ship drill (shipworm, Teredo navalis) lives in warm to temperate zones in salt water. It can cause damage wherever suitable wooden structures are in the water. It has been carried around the world by wooden ships. Fortunately, the shipworm does not exist in the not very salty, cool Baltic Sea. Otherwise we would not be able to admire the baroque Wasa from 1628 in its museum in Stockholm.
It was not until the end of the 18th century that ships were regularly shod with copper plates, which protected against the drill worm, but did not always last long enough.
 Such privateers were very similar to pirates, only that they had to confine themselves to the ships of enemy countries when they were captured.
(1) Wikipedia "Alexander Selkirk".
(2) “Stranded in Paradise”, Der Spiegel from 2. 2. 2009, on the 300th anniversary of the rescue of Alexander Selkirk.