Collective nouns for animals are often playful: a parliament of owls, a murder of crows, a tower of giraffes and a flamboyance of flamingos. Many date back to hunting books from the 15th century.

Its earliest known printed use is in Dr. Seuss’s “If I Ran the Zoo” (1950), as the name of a small, grumpy creature. Within a year it was being used as slang for a boring or square person.

No horned Viking-age battle helmet has ever been found. The image became popular in the 19th century through Romantic art and costume designs for Wagner’s operas.

Czech writer Karel Čapek introduced “robot” in his 1920 play R.U.R. The word comes from the Czech “robota”, meaning forced labour — the artificial workers in the play eventually rebel.

Scottish inventor Alexander Bain patented an electric printing telegraph that could transmit images in 1843 — more than 30 years before Alexander Graham Bell’s telephone patent in 1876.

Douglas Engelbart and Bill English built the first prototype in 1964: a wooden shell with two metal wheels and a single button. Engelbart showed it to the world in the 1968 “Mother of All Demos”.

It had 2,048 words of erasable memory and about 36,000 words of fixed “rope” memory woven by hand. A basic calculator today has more processing power.

Ada Lovelace published notes on Charles Babbage’s proposed Analytical Engine in 1843, including a method for calculating Bernoulli numbers — widely considered the first published algorithm intended for a machine.

The Linux kernel team used a proprietary tool called BitKeeper for free until the licence was revoked. Linus Torvalds wrote Git as a replacement in 2005; within a few months it was managing the kernel.

On 25 August 1991 Linus Torvalds posted that he was making a free operating system — “just a hobby, won’t be big and professional like gnu”. Today Linux runs most web servers, all of the world’s top supercomputers and Android phones.

Guido van Rossum began Python as a hobby project over the Christmas holidays of 1989 and released version 0.9.0 in February 1991 — the same year Linux was announced.

Introduced around 2010, SAP HANA stores data primarily in RAM and in columns rather than rows, which makes large analytical queries far faster than traditional disk-based databases. It is the foundation of SAP S/4HANA.

The company’s name originally stood for “Systemanalyse Programmentwicklung” and later “Systeme, Anwendungen und Produkte in der Datenverarbeitung” — Systems, Applications and Products in Data Processing.

Formulas can also nest up to 64 levels of functions. If you ever get close to either limit, it is a strong sign the logic belongs in LET, a helper column or Power Query instead.

The old .xls format capped sheets at 65,536 rows and 256 columns (IV). Excel 2007’s .xlsx format raised it to 1,048,576 rows and 16,384 columns — 1,024 times more cells.

In the default Windows date system, 1 January 1900 is day 1 and each day adds 1, so dates are just formatted numbers. That is why you can subtract two dates to get the days between them, and why a date turns into something like 45,000 when formatting is lost.

DATEDIF calculates the difference between two dates in days, months or years. It came from Lotus 1-2-3 compatibility, does not appear in Excel’s function autocomplete, yet still works in every version.

“Me at the zoo”, uploaded by co-founder Jawed Karim on 23 April 2005, shows him in front of the elephants at San Diego Zoo. It has since been viewed hundreds of millions of times.

Larry Page and Sergey Brin’s 1996 research search engine analysed backlinks to judge a page’s importance, hence “BackRub”. It was renamed Google, a play on “googol” (1 followed by 100 zeros), in 1997.

Wi-Fi is a brand name created by a marketing agency for the Wi-Fi Alliance as a catchier name than “IEEE 802.11b Direct Sequence”. The “Wireless Fidelity” expansion was added later by the Alliance and then dropped.

Tim Berners-Lee published the first web page at CERN in 1991. CERN has restored it at its original address, info.cern.ch, where you can still read how the web was supposed to work.

Gary Thuerk, a marketer at Digital Equipment Corporation, sent an advertisement for new computers to a few hundred users on ARPANET, the forerunner of the internet. It caused complaints — and reportedly some sales.

He was about 1.68–1.70 m tall — average or slightly above for a Frenchman of his time. The myth came from confusion between French and British inches, his nickname “le petit caporal” (a term of affection) and British cartoonists who drew him tiny.

The Anglo-Zanzibar War of 27 August 1896 lasted roughly 38 to 45 minutes. British ships bombarded the palace after the new sultan refused to stand down, and a ceasefire followed within the hour.

These half-millimetre “water bears” can dry out into a dormant state. In 2007 some were carried into orbit on the outside of a spacecraft and exposed to vacuum and radiation; a number of them revived and even reproduced after returning to Earth.

Butterflies have taste receptors on their feet. A female landing on a leaf can “taste” it to check whether it is the right plant for her caterpillars before laying eggs.

Astronomers noticed Uranus drifting from its predicted path. Urbain Le Verrier calculated where an unknown planet must be pulling it, and in 1846 Johann Galle found Neptune within about one degree of that prediction on his first night of looking.

A Martian solar day, called a “sol”, lasts about 24 hours and 39 minutes. Mission teams working with rovers have lived on Mars time, shifting their schedule by about 40 minutes every day.

It is very long but only a few metres wide and made of materials that blend into the landscape. Astronauts, including China’s first astronaut Yang Liwei, have said they could not see it unaided from orbit. Cities and airports at night are far easier to spot.

Claude Shannon estimated the number of possible chess games at around 10^120. The observable universe is estimated to contain about 10^80 atoms. Even a computer checking a billion games a second since the Big Bang would not get anywhere close.