Computer

On a leap-second day, the last minute can have 61 seconds. To keep UTC close to Earth’s rotation, clocks may insert 23:59:60 after 23:59:59. Because that extra second can disrupt computer systems, global timekeepers plan to change the system by 2035.

In 2014, Psy's "Gangnam Style" overflowed YouTube's view counter. YouTube stored views as a 32-bit integer, capped at 2,147,483,647. When the video passed it, YouTube switched to a 64-bit counter. Contrary to the myth of a panicked rewrite, Google had foreseen it.

SETI@home used volunteers' idle computers to scan space for extraterrestrial signals. Aimed at 50,000–100,000 machines, it drew 5.2 million participants and logged over 2 million years of computing—about 50x faster than the world's top supercomputer in 2013.

When an acronym expands to include itself — like GNU (GNU is Not Unix), PHP (PHP: Hypertext Preprocessor), and YAML (YAML Ain't Markup Language) — it's called a recursive acronym. PHP was originally Personal Home Page Tools before being redefined.

Tim Berners-Lee, the father of the Internet, apologized for adding "//" to "http://". He said "http:" alone would have sufficed, but he added the slashes because "it looked cool at the time."

Bill Burr, who wrote the 2003 NIST guidelines recommending passwords mix uppercase, numbers, and special characters, later said he regretted it — his reference material was from the 1980s. Experts now say long passphrases of multiple words are both safer and easier to remember.

The standard test image in computer image processing comes from a 1972 Playboy magazine. A researcher cropped Lena Forsen's photo for a paper, and it became the field's benchmark, earning her the nickname "First lady of the internet."

Test Computer content with wiki links.