Last name Cailliau (Cailliau 
, Кайо 
, 卡里奥) , across the world, is quite a rare family name. The cognomen Cailliau is habitual in Western Europe, particularly Belgium, where it is quite a rare surname, Luxembourg, and France. Not in comparison with a country's population, it is the most numerous in France, Belgium, and the United States. Very seldom, Cailliau is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Cailliau | Belgium, Canada, France, United States, Portugal |
| Кайо | Ukraine, Russia |
| alfred cailliau Belgian engineer, BE (b. 1877) |
|
|
|
robert cailliau Belgian engineer, computer scientist, and co-inventor of the World Wide Web, BE (b. 1947) |
|
| michel cailliau French writer (1913-2000), FR (b. 1913) |
|
|
| charles cailliau BE (b. 1916) |
|
|
| bernard cailliau French politician, FR (b. 1958) |
|
|
| ariane cailliau botanist (b. 1977) |
|
|
| katia cailliau researcher ORCID ID = 0000-0001-7993-8437 |
|
|
| katia cailliau researcher (ORCID 0000-0003-1772-1034) |
|
|
| maurits cailliau BE |
|
Mr, Léa, Joan, Joel, Jens, Jean, Noah, Eddy, Eric, Herv, Hugo, Frã, Ilse, Ivan, Ides, Ward, Marie, Marin, Manon, Mieke, Sarah, Simon, Léo, Suzan, Lynn, Liam, Ms, Max, Sã, Ann, Cã, Pam, Rik, Guy, Luc, Evy, Ian, Marc, Mado, Alex, Anne, Aude, Axel, Paul, Rene, Daan, Lise, Luka, and Alice