Creating CAPTCHA

Creating CAPTCHA

In 2000, as the internet expanded, websites faced a growing challenge to stop spam bots from flooding their systems.

To separate humans from machines, researchers at the United States’ Carnegie Mellon University in Pittsburgh, Pennsylvania, created the Completely Automated Public Turing test.

From its early development to its evolution into reCAPTCHA it continues to block millions of automated attacks every day.

Ashley Byrne speaks to computer scientist Andrei Broder, who played a key role in developing the concepts that helped shape this technology.

A Made in Manchester production.

Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from the death of Adolf Hitler, the first spacewalk and the making of the movie Jaws, to celebrity tortoise Lonesome George, the Kobe earthquake and the invention of superglue. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: Eva Peron – Argentina’s Evita; President Ronald Reagan and his famous ‘tear down this wall’ speech; Thomas Keneally on why he wrote Schindler’s List; and Jacques Derrida, France’s ‘rock star’ philosopher. You can learn all about fascinating and surprising stories, such as the civil rights swimming protest; the disastrous D-Day rehearsal; and the death of one of the world’s oldest languages.

(Photo: I am not a robot. Credit: Stock image / Vector Illustration)

Avsnitt(2000)

Martín Chambi: Peru's pioneering documentary photographer

Martín Chambi: Peru's pioneering documentary photographer

Martín Chambi is regarded as one of the most important indigenous Peruvian photographers of the 20th century. Famous for his black and white images of local Andean people and the surrounding countryside, Chambi’s work challenged preconceptions of Peruvian culture and traditions. In 1924 he was among the first to photograph Machu Picchu – his work helping to shape the way Peru is seen around the world. His photography was declared part of the Cultural Heritage of the Nation by Peru’s government in 2019. Jacqueline Paine speaks to his grandson Roberto Chambi.Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: Martín Chambi self-portrait 1923. Credit: Martín Chambi Archive.)

21 Maj 10min

Nigerian photographer’s iconic 'Hairstyles' series

Nigerian photographer’s iconic 'Hairstyles' series

J. D. 'Okhai Ojeikere, who was known as Nigeria’s top photographer, started documenting women’s hairstyles in 1968. He built up a portfolio of around 2,000 negatives revealing the elaborate ways African women styled their hair through his series of black and white photos. A selection of his 'Hairstyles' prints was displayed at the Venice Biennale in 2013. Reena Stanton-Sharma speaks to his son Amaize Ojeikere, also a photographer, about his father’s work. Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: 'Hairstyles' by J. D. 'Okhai Ojeikere. Credit: TERESA SUAREZ/EPA-EFE/REX/Shutterstock)

20 Maj 10min

Gander: The Kindness of a Canadian Town after 9/11

Gander: The Kindness of a Canadian Town after 9/11

On 11 September, 2001, a small Canadian town called Gander became a haven for thousands of airline passengers and crew stranded after the 9/11 terrorist attacks. The attacks on the World Trade Center had forced the closure of US airspace leaving many flights unable to land. Within hours, 38 planes with 7,000 passengers, had been diverted to Gander, effectively doubling the town's population. But what happened next showcased the extraordinary kindness and generosity of the Newfoundlanders. For five days, local residents provided beds, food, medicine and clothing for those stranded during the crisis, and didn’t ask for a penny. They even put on music evenings, barbecues and canoe trips to keep their visitors entertained.

19 Maj 10min

Sweden’s shocking sugar experiment

Sweden’s shocking sugar experiment

In the 1940s, some vulnerable Swedish hospital patients were fed large amounts of sugary sweets as part of an experiment to see what it would do to their teeth. Researchers considered the study a success as it led to new recommendations for children to eat sweets just once a week. In the 1990s, the unethical aspects of the experiment emerged when Elin Bommenel became the first researcher to gain access to the original documents from the experiments. Sweden's government has never formally apologised for what happened, although it has greatly improved care for vulnerable children and adults.Elin tells Frida Anund about the revelations. A PodLit production. Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: A sugar cube. Credit: Getty Images)

16 Maj 9min

Mexico’s soda tax: Confronting soft drink giants

Mexico’s soda tax: Confronting soft drink giants

In 2013, Mexico’s government approved a tax on sugary soft drinks. The country has one of the highest rates of fizzy drink consumption in the world. Some rural homes do not have access to safe drinking water and a third of schools do not have drinking water. Consequently, carbonated drinks would be sold in schools across the country. Grace Livingstone speaks to Dr Simon Barquera, director of health and nutrition research at Mexico’s Institute of public health. He faced intimidation and spying attempts for advocating the tax.Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: Sugary drinks. Credit: PA)

15 Maj 10min

The founding of the Warsaw Pact

The founding of the Warsaw Pact

On 14 May 1955, the leader of the Soviet Union and leaders from seven European countries met to sign the Warsaw Pact. In the years following World War Two, the Soviet Union and the United States started the worldwide Cold War. While Western powers feared the spread of communism, the Soviets worried about US atomic bombs. What resulted was the formation of the North Atlantic Treaty Organisation (NATO) in 1949. The Warsaw Pact was signed six years later in response to West Germany joining NATO. Natasha Fernandes uses archive of East Germany’s leader Otto Grotewohl to tell the story.Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: Soviet Premier, Nikolai Bulganin (centre) addresses Soviet leaders at the Warsaw Conference on 14 May 1955. From left to right: Marshal Ivan Koniev, Minister Vyacheslav Molotov, Bulganin and Marshal Gregori Zhukov. Credit: Bettmann via Getty images)

14 Maj 10min

Tesla and Edison: Electricity rivals

Tesla and Edison: Electricity rivals

By 1915, the two great rivals, Nikola Tesla and Thomas Edison, had brought electricity to the world. It was reported that they were set to share the Nobel Prize for Physics, but it never happened. In 2011, Claire Bowes spoke to Tesla’s biographer Mark Seifer and relative William Terbo.Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: Nikola Tesla in c.1896 and Thomas Edison in 1893. Credit: Bettmann and SSPL/Getty Images)

13 Maj 10min

Intervision Song Contest

Intervision Song Contest

In 1980, Finnish singer Marion Rung won the Intervision Song Contest. Born in the 1960s, Intervision was the Eastern Bloc’s answer to Eurovision. It ran until 1980, although in 2025 Russia’s President Vladimir Putin ordered its revival. Finland, which maintained neutrality during the Cold War, was one of the few countries to participate in both competitions. Marion Rung achieved top 10 Eurovision finishes in 1962 and 1973 before winning Intervision. She speaks to Ben Henderson.Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from football in Brazil, the history of the ‘Indian Titanic’ and the invention of air fryers, to Public Enemy’s Fight The Power, subway art and the political crisis in Georgia. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: visionary architect Antoni Gaudi and the design of the Sagrada Familia; Michael Jordan and his bespoke Nike trainers; Princess Diana at the Taj Mahal; and Görel Hanser, manager of legendary Swedish pop band Abba on the influence they’ve had on the music industry. You can learn all about fascinating and surprising stories, such as the time an Iraqi journalist hurled his shoes at the President of the United States in protest of America’s occupation of Iraq; the creation of the Hollywood commercial that changed advertising forever; and the ascent of the first Aboriginal MP.(Photo: Marion Rung performing at the Intervision Song Contest in 1980. Credit: Juha Jormanainen/Shutterstock)

12 Maj 10min

Populärt inom Samhälle & Kultur

podme-dokumentar
aftonbladet-krim
rattsfallen
svenska-fall
p3-dokumentar
en-mork-historia
nemo-moter-en-van
skaringer-nessvold
creepypodden-med-jack-werner
killradet
kod-katastrof
flashback-forever
hor-har
p1-dokumentar
vad-blir-det-for-mord
aftonbladet-daily
historiska-brott
p3-historia
olyckan-inifran
rss-brottsutredarna