You have to be careful not to put too much stock in it. Hemispheric dominance is really more a myth than anything else. Certain areas of the brain are in fact geared more towards different things, but overall, every function your brain performs takes place in multiple regions.
If you dont distinguish the work of any hemisphere, you cannot know how your brain works. With no left hemisphere you cant understand of written, spoken or any other language
Because there is evidence that there is no specialisation of each hemisphere, but rather transient hemisphere dominance may occur depending on how difficult the task is. eg, visuospatial ability is attributed to the right hemisphere, but the left hemisphere is also invloved when it is an easy task and the right hemisphere may do more work only when it is a difficult visuospatial task.