Twitter has told its 330 million users to change their passwords after a computer bug was identified.
It meant some passwords were stored in plain text on its internal computer system.
The company insists the problem's been fixed, and says there's no indication that passwords were stolen or misused.
Tech expert Jess Kelly says there's no cause for panic: 'Usually when passwords are stored they're what's called 'hashed' so that means they're not legible. In this instance some of the passwords were stored in plain text. There's no indication that the passwords were stolen, it's just advisable that you change your password'.
