Lateral thinking is about moving sideways when working on a problem to try different perceptions, different concepts and different points of entry. The term covers a variety of methods including provocations to get us out of the usual line of thought. Lateral thinking is cutting across patterns in a self-organising system, and has very much to do with perception.
For example: Granny is sitting knitting and three year old Susan is upsetting Granny by playing with the wool. One parent suggests putting Susan into the playpen. The other parent suggests it might be a better idea to put Granny in the playpen to protect her from Susan. A lateral answer!
The term "Lateral thinking" can be used in two senses: