this refers to person's perception of personal control over their own behaviour, it is measured along a dimension of 'high internal' to 'high external'
high internals perceive themselves as having a great deal of personal control over their behaviour and are therefore more likely to take personal responsibility. what happens to a person is seen as a product of their own ability and effort.
high externals perceive their behaviour as being caused more by externl influences or luck.
internal take responsibility for their own actions and are less likely to be influenced by others and so more likely to be independent
high internals are achievements orientated and so more likely to become leaders and therefore be independent
high internals are likely to have confidence and do not need external approval. As a result, they do not need to conform and less likely to obey.