Theo (1928–2019) and Ora (1931–2021) Coster (Hebrew: תיאו ואורה קוסטר) are the founders of Theora Concepts; they were a married Israeli couple and inventors of about 200 games and toys including Guess Who?, Magimizer, Zingo!, and Go Pop.
[2] He survived the Holocaust by living with a non-Jewish family and changing his name.
[3][2] After graduating college and serving in the Dutch military, he moved to Israel in 1955 where he met Ora, a schoolteacher.
[1][4] As a teenager, Ora had served in the Israeli Army during the 1948 war[4] She then moved to the United Kingdom to study stage design.
They began by creating promotional products for businesses until they made enough money from selling over 12 billion Elsie Stix (an ice cream stick which doubled as a construction toy) to let them focus on designing games.