Bank holiday bunting appears automatically on the GOV.UK website thanks to a little program! If you’re reading this post today (Monday 21 April 2025) it’s Easter Monday which is a Bank Holiday in England & Wales and in Northern Ireland you have a chance to see it.
The UK Government’s website has a UK Bank Holidays page which lists all the upcoming dates for the next two years’ worth of bank holidays (so people can put them in the diaries) for England & Wales, Northern Ireland and Scotland (the different UK nations share many but not all bank holidays).
But… if you visit the page on a Bank Holiday then you may be met with some bunting, which doesn’t appear if you visit the page on a non-bank holiday day. People who look after the website added in this little Easter egg* over a decade ago and people have been discovering it ever since. They use an Application Program Interface (API) which connects the bank holiday website to a database which lets the website check, whenever there’s a bank holiday, whether it should display bunting. For example Easter Monday is a celebratory day in the Christian calendar but Good Friday isn’t. Both are holidays but it wouldn’t be appropriate for bunting on Good Friday so it gets the instruction “bunting: false” whereas Easter Monday is “bunting: true”. You can see the API’s instructions here.
If you’re reading this post after Easter Monday 2025 you still have more chances to catch the bunting on the Early May bank holiday, the Spring bank holiday, though then you’ll need to wait until August for the Summer bank holiday then a few more weeks before Christmas Day, Boxing Day and New Year’s Day and New Year’s Day – on those days the bunting changes to tinsel!
*it’s not called an Easter egg because it’s there at Easter, the bunting is there at other times too but because it’s something to discover (like Easter Egg Hunts – find ours at The CS4FN Easter Egg Hunt).
– Jo Brodie, Queen Mary University of London
This is an updated version of a snippet that appeared previously on this blog.
Part of a series of ‘whimsical fun in computing’ to celebrate April Fool’s (all month long!).
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This blog is funded by EPSRC on research agreement EP/W033615/1.
The first ever half marathon allowing humanoid robots to run against humans was held in Beijing this weekend (April 2025). 12,000 humans ran the event alongside 21 robots…and for now the humans definitely are the winners.
A robot called Tiangong Ultra, was the robot winner, one of 6 robots that managed to finish. It completed the half marathon in just over 2 hours, 40 minutes. The fastest human, for comparison, finished in 1 hour 2 minutes and Jacob Kiplimo, of Uganga holds the half-marathon world record at 56 minutes 42 seconds set in Feb 2025 in Barcelona. The first world record from 1960 being 1 hour 7 minutes. The robots, therefore, have a long way to go.
The robots struggled in various ways (see video link below) reminiscent of human runners such as over-heating and finding it hard to even keep standing (though for humans the latter usually only happens towards the end, not on the start line as with one robot!). While humans need to constantly take water and nutrients, the winning robot similarly needed several battery changes. It’s winning performance was put down to it copying the way that human marathon runners run by Tang Jian, chief technology officer from the Beijing Innovation Centre of Human Robotics who built it. It also has relatively long legs which also is certainly an advantage to human runners (given it had mastered standing in the first place on such long legs).
Totally autonomous marathon running is relatively difficult for a machine because it takes physical ability, including dealing with kerbs, rough road surfaces and the like but also navigating the course and avoiding other runners. In this race the robots each had a team of human ‘trainers’ with them, in some cases giving them physical support, but also for safety (though one took out its trainer as it crashed into the side barriers!)
So the robots still have to make a lot of progress before they take the world record and show themselves to be superhuman as runners (as they have already done in games including chess, go, poker, jeopardy and more). Expect the records to tumble quickly, though, now they have entered the race.
Of course, a robot does not need to run on 2 legs at all, apart from due to our human centred preferences. Whilst it is a great, fun challenge for robotics researchers that helps push forward our understanding, it is plausible that the future of robotics is in some other form of locomotion: centipede-like perhaps with hundreds of creepy crawly legs, or maybe we will settle on centaur-like robots in the future (four legs being better than two for stability and speed). After all evolution has only settled on 2 legs because it has to work with what came before and standing upright is a way to free up our hands to do other things…so if designing from scratch why not go for 4 legs and 2 arms.
So the future of robot marathons is likely to involve a large number of categories from centipedal all the way down to humanoid. Of course, expect robot Formula 1 for wheeled self driving robots too in any future robot olympics. Will other robots ever enjoy watching such sport? That remains to be seen.
Anne-Marie Imafidon was recently awarded the Society Medal by the British Computer Society for her work supporting young women and non-binary people of all ages into Science, Technology, Engineering and Maths (STEM) careers.
Born and raised in East London, Anne-Marie became the youngest girl to pass A-Level Computing at the age of 11 and she was only 20 when she passed a Master’s degree in Maths and Computer Science from Oxford University! She went on to work in industry but realised there was a big problem in how few women there were both studying STEM subjects and so taking up careers, despite there being no good reason why they shouldn’t enjoy such subjects and careers.
Using her entrepreneurial skills, and industry contacts, she decided to do something about it. In 2013 she therefore founded STEMettes a social enterprise (a business aiming to do good for society rather than just make money like most companies). It aims to inspire and support young women and non-binary people in STEM now extended to STEAM so including the arts as well. Since then it has reached over 73,000 young people. They do this by running all kinds of events like programming hackathons solving real world problems in teams, STEAM clubs, panel sessions where women share and non-binary role people act as models sharing their experiences and advice, school trips to STEAM offices, run courses in programming and cyber security, run competitions and lots.
Anne-Marie has campaigned tirelessly for equity in the tech workplace, raising the profile of under-represented groups in industry and commerce so is a really deserving winner of the BCS award that recognises people who have made a major contribution to society.
– Jane Waite and Paul Curzon, Queen Mary University of London
This is an extended version of an article that first appeared on our Teaching London Computing Site.
Easter eggs can be chocolate but they are also hidden treasures to be found in games, websites, other software (and now even Lego sets). Especially for Easter we have hidden an Easter Egg in one of our diversity linked pages. Can you find it? Enjoy the hunt! (But if you do find it don’t give it away and spoil the fun for others. Just be quietly pleased at how clever you are!)
The term Easter Egg was coined after Warren Robinett hid the message “Created by Warren Robinett” in the Atari game, Adventure, that he created. He did it as part of a plan he hatched to protest against the Atari policy of the time of not crediting the developers of their games – supposedly so their best people wouldn’t get poached by rivals!! The real purpose of the game was to find a hidden chalice, but the hidden message could be found if the player’s avatar (a square block) stopped over one specific pixel (“the gray dot”) in one specific place in the game.
It was only found (by a player) after Warren had left the company (he hadn’t let on to the management what he had done even when he resigned). Originally the company scrambled to try to re-release the game without the message, but given how expensive that would have been to do, instead they turned it into a feature to whip up more excitement around their games and started to hide similar surprises in other games from then on, calling them Easter Eggs.
As an aside, the wonderful book, Ready Player One by Ernest Cline is based on a plot around finding Easter Eggs. It is a must read for anyone interested in 1980s technology, easter eggs and what a metaverse might one day be actually like to live in. All computer scientists should read it (and only then watch the film which is good, but not as good.)
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This blog is funded by EPSRC on research agreement EP/W033615/1.
Hint – we think you will never see it without some help.
Mark Rober, an engineer and YouTuber who worked for NASA, has created a dartboard that jumps in front of your dart to land you the best score. Throw a dart at his board and infra-red motion capture cameras track its path, and, software (and some maths) predicts where it will land. Motors then move the dartboard into a better position to up the score in real time!
To track the dart Mark used a motion-capture system with six cameras that respond to infrared instead of light (this let the cameras follow the movement of just the dart, which had a special infrared reflecting surface, and not all the other stuff in the room that would distract a light-sensing camera). He used Matlab to program the maths needed to calculate (very quickly!), from the parabolic path the dart was flying in, where it was about to land, so that the dart board could be moved into place and meet it. The movement of the darts board was controlled by fishing wire (literally) and small motors to pull the board left, right, up or down under the control of an Arduino.
Possibly the most ridiculously over-engineered thing but a lot of fun, even if a bullseye isn’t the highest possible score on a dart board (hitting the bullseye gives you 50 points but landing your dart in the triple 20 segment gives you 60!)
An earlier version of this post originally appeared both on this blog and on the back page of issue 28 of the CS4FN magazine, Cunning Computational Contraptions, a fun look at the history of computational devices which you can download as a PDF from the link below.
This issue of the magazine contains articles about automata, core rope memory (used by NASA in the Moon landings), Charles Babbage’s Analytical Engine (never built) and Difference Engine made of cog wheels and levers, mercury delay lines, standardising the size of machine parts, Mary Coombs and the Lyons tea shop computer, computers made of marbles, i-Ching and binary, Ada Lovelace and music, a computer made of custard, a way of sorting wood samples with index cards and how to work out your own programming origin story….
Part of a series of ‘whimsical fun in computing’ to celebrate April Fool’s (all month long!).
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This blog is funded by EPSRC on research agreement EP/W033615/1.
Video games can be a very successful way to do citizen science, getting ordinary people involved in research. Sea Hero Quest is an extremely successful example. It involves a boy setting out on a sea quest to recover his father’s memories, lost when he suffers from dementia. The hundreds of thousands of people joining the quest have helped researchers better understand our ability to navigate.
The Sea Hero Quest project was led by Deutsche Telecom, working with both universities and Alzheimer’s Research UK. The first mass-market game of its kind, it has allowed researchers to explore navigation and related cognitive abilities of people throughout their lives. The game has 75 levels, each with different kinds of task in different environments, and has been played by millions of people around the world for over a 100 years of combined game time. The amount of data collected is vast and would have taken researchers centuries to collect by traditional means, if possible at all.
For example, an international team including researchers from UCL, the University of Lyon and the University of Münster used the game to explore how the place people grew up affects their ability to navigate. As well as more general data from around 400,000 people across the world, they also used the data specifically from people who had completed all levels of the game. This amounted to around ten thousand adults of all ages.
They found that people are best at navigating in situations similar to where they grew up (where they lived at the time of playing the game had no effect). So, for example, people who grew up in an American grid-like city such as Chicago, were better at navigating in grid-based levels. Those who grew up in cities such as Prague in Europe, where the streets are more wiggly and chaotically laid out, were better at levels needing similar navigation skills. Throughout, the researchers found that those that grew up in the countryside were better at navigating overall as well as specifically in more unstructured environments.
Sea Hero Quest shows that games designers, if they can create fun but serious games, can help us all help researchers…It is often said that playing video games is bad for growing brains but it also shows that the way we design our cities affects the way we think and can be bad for our brains!
Robert Weitbrecht was born deaf. He went on to become an award winning electronics scientist who invented the acoustic coupler (or modem) and a teletypewriter (or teleprinter) system allowing the deaf to communicate via a normal phone call.
If you grew up in the UK in the 1970s with any interest in football, then you may think of teleprinters fondly. It was the way that you found out about the football results at the final whistle, watching for your team’s result on the final score TV programme. Reporters at football grounds across the country, typed in the results which then appeared to the nation one at a time as a teleprinter slowly typed results at the bottom of the screen.
Teleprinters were a natural, if gradual, development from the telegraph and Morse code. Over time a different simpler binary based code was developed. Then by attaching a keyboard and creating a device to convert key presses into the binary code to be sent down the wire you code type messages instead of tap out a code. Anyone could now do it, so typists replaced Morse code specialists. The teleprinter was born. In parallel, of course, the telephone was invented allowing people to talk to each other by converting the sound of someone speaking into an electrical signal that was then converted back into sound at the other end. Then you didn’t even need to type, never mind tap, to communicate over long distances. Telephone lines took over. However, typed messages still had their uses as the football results example showed.
Another advantage of the teletypewriter/teleprinter approach over the phone, was that it could be used by deaf people. However, teleprinters originally worked over separate networks, as the phone network was built to take analogue voice data and the companies controlling them across the world generally didn’t allow others to mess with their hardware. You couldn’t replace the phone handsets with your own device that just created electrical pulses to send directly over the phone line. Phone lines were for talking over via one of their phone company’s handsets. However, phone lines were universal so if you were deaf you really needed to be able to communicate over the phone not use some special network that no one else had. But how could that work, at a time when you couldn’t replace the phone handset with a different device?
Robert Weitbrecht solved the problem after being prompted to do so by deaf orthodontist, James Marsters. He created an acoustic coupler – a device that converted between sound and electrical signals – that could be used with a normal phone. It suppressed echoes, which improved the sound quality. Using old, discarded teletypewriters he created a usable system Slot the phone mouthpiece and ear piece into the device and the machine “talked” over the phone in an R2D2 like language of beeps to other machines like it. It turned the electrical signals from a teletypewriter into beeps that could be sent down a phone line via its mouthpiece. It also decoded beeps when received via the phone earpiece in the electrical form needed by the teleprinter. You typed at one end, and what you typed came out on the teleprinter at the other (and vice versa). Deaf and hard of hearing people could now communicate with each other over a normal phone line and normal phones! The idea of Telecommunications Device for the Deaf that worked with normal phones was born. However, they still were not strictly legal in the US so James Marsters and others lobbied Washington to allow such devices.
The idea (and legalisation) of acoustic couplers, however, then inspired others to develop similar modems for other purposes and in particular to allow computers to communicate via the telephone network using dial-up modems. You no longer needed special physical networks for computers to link to each other, they could just talk over the phone! Dial-up bulletin boards were an early application where you could dial up a computer and leave messages that others could dial up to read there via their computers…and from that idea ultimately emerged the idea of chat rooms, social networks and the myriad other ways we now do group communication by typing.
The first ever (long distance) phone call between two deaf people (Robert Weitbrecht and James Marsters) using a teletypewriter / teleprinter was:
“Are you printing now? Let’s quit for now and gloat over the success.”
Do you know how to make a sandwich? More importantly do you know how to write down a set of precise, detailed instructions that could tell someone else how to make a sandwich? I’m sure you think you could, but after watching this video below you might feel less sure.
This video has been used in some classrooms as a fun way of talking about how precise and correct an algorithm needs to be in order to run a program correctly. Josh, the dad in the video, asks his children (Johnna and Evan) to write out some instructions to make a peanut butter and jelly (jam) sandwich. They all speak the same language (English) so the instructions don’t have to be converted into machine language for the computer (dad) to run the program and make the sandwich, but as you’ll soon see, it’s harder than his children think. They do get there in the end though… kind of.
See if you can write your own set of instructions and then get someone to follow them exactly.
Incidentally, the image used to illustrate this article has been “…assessed under the valued image criteria and is considered the most valued image on Commons within the scope: peanut butter and jelly sandwiches. You can see its nomination here.” Only the best peanut pics on this site! You can see all the images that didn’t win here.
Kew Gardens‘ 404 error page (click here to see it) says “Oops! 404 error. We’ve been doing a bit of website weeding. The content on this page has been uprooted and planted elsewhere. Please keep digging.” The page helpfully links to other pages on their site. Flowers Image by 👀 Mabel Amber, who will one day from Pixabay with writing added by CS4FN.
Have you ever seen a website say “404 – page not found” or something very similar? This can happen if a page has since been moved or deleted, or if you’ve typed the address wrongly so the page can’t be loaded. Most of the time the error messages are fairly dull – some of them might even be slightly useful and point you to the homepage or let you search the website to try and find the page you were looking for.
Sometimes organisations make a bit of an effort and produce an error message that is also entertaining, though, adding delight to the user experience design. For example Kew Gardens keeps the ‘garden’ theme going in its message, and Innocent Drinks has a whole page describing previous errors that the company has made. Lego‘s 404 not found page has a picture of a minifigure dressed as a construction worker who’s looking a bit worried and the page says “We’ll try not to lose our head over this, but if we do… we’ll put it back on.”
‘404’ has become the universal language of ‘something that is not found or cannot be found’. If you are ever in a computer science department that happens to have a Room 404 there’s a very high chance that someone will have jokingly added a post-it note saying “Room not found”.
Incidentally if you were to search on Google Maps for CS4FN’s building (the Peter Landin teaching rooms, originally called the Bancroft Road Teaching Rooms) you’d find that someone has changed our address to 404 Bancroft Road (click the link to see if it hasn’t been changed back since). We’re not sure who did it or why but we’re fairly sure a computer scientist in the department was behind it.
Why “404”?
There may be different reasons that a website can’t load a page and sometimes it can be helpful to know why. You might be reassured to know that the problem isn’t anything to do with you, and to be told that the server that is hosting the pages is busy or down for maintenance and you should come back later. Rather helpfully there is a list of agreed “server response codes” so that whenever a page won’t load a differently numbered message appears depending on the reason.
There are quite a lot of these messages and they all have three digits. If the digit starts with the number 4 then it means that the problem may have come from the user (such as you typing in a web address wrongly so being given the 404 message). If it starts with the number 5 it means a problem on the server’s side and it’s not probably going to be able to show you pages because of a fault. You might also have seen “Error 503 – Service unavailable” – that’s usually a temporary fault just try again later.
Making 404 pages more useful
In 2012 a group of organisations that helps raise awareness about missing children encouraged companies to add some helpful information to their 404 pages so that every time someone landed on their ‘wrong’ page they’d be shown a name and photograph and any relevant information about someone the police and emergency services were trying to locate, and who to call if they knew who they were. What a great idea!
– Jo Brodie, Queen Mary University of London
Part of a series of ‘whimsical fun in computing’ to celebrate April Fool’s (all month long!).
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This blog is funded by EPSRC on research agreement EP/W033615/1.
Wheel Barometer, also known as Banjo Barometer, Barnasconi, Leeds, c. 1810 – Museum of Science and Industry (Chicago), via Wikimedia Commons under a CC0 licence.
There’s an old science joke about a physics professor who gives, as weekend homework, the task to use a barometer* to measure the height of the physics building. Back in class on Monday the professor invites the students to share their working. The class discuss how they measured the pressure at the base of the building, climbed to the top and measured it again then used a mathematical formula to work out the height. One of the students admitted that he’d saved a bit of time, measurements and calculations by simply knocking on the door of the janitor’s office and saying “If you will tell me the height of this building, I will give you this beautiful barometer.“
Social engineering
One of the simplest and often quickest ways to ‘hack’ into someone’s account doesn’t involve any hacking (or cracking) at all. People lose lots of money, time and anxious sleep to mistakes made because they were distracted and fell for something which was cleverly designed to fool them. Most cyberattacks happen not because someone guessed a password but because someone willingly handed it over.
Phishing attempts can involve little more than making a fake website look like a real one and hoping people don’t notice that the address doesn’t look right. Someone clicks on the link, perhaps in an email or a text message telling them that there’s something wrong with their account that they need to deal with urgently, and enters their email address and password – handing their account details to the scammer. Worse, when people re-use an email address with the same password on multiple sites the scammers suddenly have access to a great deal more of their private information and perhaps even access to their money (e.g. if they have stored payment details with their account).
Back in the 1980s ‘Claire’ managed to hack into a computer network with incredible ease as her son explained in a series of posts. Claire, known as someone who was ‘good with computers’, was invited to a meeting by the CEO of a company that made security systems. She visited his office, taking the lift all the way up to the penthouse office, where he offered her “an eye-watering sum” if she was able to break into his system within a week.
Offer accepted she took the lift all the way down to the building’s basement where the computer lab was. She found a stack of papers and stood outside the lab door looking busy and needing to get on with her work but struggling to get in with all the papers. One of the lab technicians helps her into the room (how kind! she’s ever so grateful!) where she makes her way to an unused computer, sits down and calls out “What’s today’s password?”. And someone tells her. It took her less than 20 minutes!
It is easy to be tricked
I (PC) was at a workshop about security. As part of it we were shown a website that could tell you how safe your password was. It gave an estimate of how long any password could be cracked in. If you typed in 1234 then it would tell you that was cracked in fractions of seconds. A word in any dictionary (even a Tolkien one) likewise. Longer passwords would take longer than shorter ones. Mix in capitals and it would take longer still, and so on. Everyone was told to type in their passwords to find out how good they were at thinking up a password. Virtually everyone did so and many found out that their passwords were not very good… others celebrated the fact that they were good at choosing a password. However, perhaps it didn’t matter either way! Everyone who typed in an actual password had just given away their password to a website that may or may not have been secure…
Never give up your password to anyone and certainly not to a computer program. Don’t even tell others the rules you use to create one!
How do you decide a website is safe? You do not judge it by looking at the website itself. You look elsewhere to a trusted source and find information that way! Either way do not ever enter personal data and passwords into a source unless you are absolutely sure.
You can also try Take Five‘s quiz to see how ‘Scamsceptible’ (susceptible to scams) you are based on how well you slept last night and if you have lots of things on your mind distracting you. Take Five is a campaign to encourage people to pause (and take five minutes) when they get a message they’re not sure about and double-check that it’s genuine.
– Jo Brodie and Paul Curzon, Queen Mary University of London
Part of a series of ‘whimsical fun in computing’ to celebrate April Fool’s (all month long!).
Subscribe to be notified whenever we publish a new post to the CS4FN blog.
This blog is funded by EPSRC on research agreement EP/W033615/1.
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