What is a Line - This Project Needs Rules!

Yes rules! We have been asked to write out 3 rules which our projects must obey. This is not a bad thing, of course, it just sounds bad; like a brief within a brief. But really it will be quite helpful i imagine. It will give me a chance to stop my ideas wandering off towards the end of the brief, a chance to nail down some really focused problems like type, layout, colour, stock ..etc.

My 3 rules will be;

1. Line must be used to represent or indicate data.
2. Text must be small so as not to interfere with the idea of the 'visualising data.' (in relation to size visuals however).
3. Key must be included to explain where the visuals may become confusing.