Two mathematicians have proved that a straightforward question—how hard is it to untie a knot?—has a complicated answer.

For years, a French mathematician searched for a proof that a gigantic number is prime. His method is still used 150 years ...

Scientists at St. Jude Children's Research Hospital have created a database that provides updated predicted structures on a ...

Animals from completely different branches of the tree of life, such as insects, worms and vertebrates, independently evolved ...

Automated email sequences are sent to users after they take specific actions, such as signing up for an email newsletter or completing a purchase. These perfectly timed and crafted emails may seem ...