The aim of the game is to gain points by creating words from the selection of eight letters given to you on-screen. Longer words give more points.
Add letters to a word by clicking on the letters or using your keyboard – then click the ‘submit’ button or press ‘enter’ when you’ve made a complete word to get the points.
At each level you are given a time limit in which to reach a target number of points. If you fail to reach the target in the allotted time, the game ends. Every five levels there is a bonus round in which you have one minute to guess the eight letter anagram – the game does not end if you fail during these bonus rounds.
Source
www.eastoftheweb.com