In the short story "A Sound of Thunder" by Ray Bradbury, Time Safari Inc. arranges safaris that allow customers to travel back in time to hunt extinct species. The story is set in the year 2055, and the company has developed a technology that allows them to send clients back in time to hunt dinosaurs.
The story's protagonist, Eckels, is a customer of Time Safari Inc. who has paid a large sum of money to go on a safari to hunt a Tyrannosaurus rex. The company provides him with a guide and all the necessary equipment to travel back in time, including special bullets that will not alter the course of history.
However, the company warns their customers to follow strict instructions and not to change anything in the past, as even the slightest alteration could have a significant impact on the future. Eckels disregards these warnings and steps off the designated path, which leads to disastrous consequences.
In summary, Time Safari Inc. arranges safaris that allow customers to travel back in time to hunt extinct species, specifically in the case of this story, dinosaurs.