It involves the internal as well as the external parameters.
Internal Processes-Internal parameters constitute of the marketing mix (Product,Place, Price Promotion), Labours, investment, machines, marketing team etc.
External Processes-External processes consist of positioning, segmentation, consumer beliefs, buying behaviour, customer relationships etc.
In external audit, the conditions of the external market are being assed and a detailed report is generated. In an external audit economic and competitive environment are being assed. For economic environment a PESTLE (Political, Economic, Social, Technological, Legal, and Environmental) analysis can be carried out. Competitive environment scan can be done by following porters five force model. By doing these the company can gauge the external environment.
For an internal audit, the company has to introspect their current processes and operations like the costs, profits, sales etc. By doing this the company can know of the existing loopholes and can find ways to close those. The company can optimize their processes after identifying the shortcomings.
A market audit is a process which needs to be continuously carried out by the company at all stages. This helps the company know where it is heading and how likely is it able to achieve its target and goals. The company can carry out such a market audit if it intends to enter new markets or wants to launch a new product. It is extremely necessary if the company is running into losses despite their diligent efforts.