An information systems audit is the process of going through a companies entire IT.  This includes:

Employees
Every job that is handled by an employee that influences the information systems of a company is broken down into total tasks and hours taken to perform tasks.  All tasks that take on a repetition are identified as being changes to an automated process run by a program.

Software
The software of the organization is identified along with the total cost.  Free alternatives to paid software are identified as viable options to cut software costs.

Servers
The servers are looked at by cost and load.  If there are 20 servers that take on very little load, then a consolidation is recommended.

A great example of one of today's greatest management information systems is Google.  From the top level they organize their overall search that allows you to manage information and break it down into sub levels.  Being able to sort through only pdf documents of Life magazine allows for a refined way to manage complex and basic information through a complicated system of servers and algorithms.

The definition of financial information system is simply the organization and structure of financial information.  Financial information systems are used primarily by banks to keep track of everything from your personal bank account to complicated loan percentages to insure that the bank is turning a profit on your money.

Large corporations also use financial information system to keep track of expenses, payroll, and daily revenue fluctuations.

Over the past decade the evolution of management information system has been influenced by several factors.  Here are the top factors of influence.

The Internet
As the internet has evolved so has the management information system.  From the early start of Yahoo and the Netscape browser to the dominance of Google and the emergence of Mozilla, the information management system has benefited from the advances within the internet.

Email
The ability to send emails back and forth allowed information to be passed on and managed through the email and POP medium.  This led to several advances within the structure and inbound systems.

Social Media
This is the next medium that will have significant influence.  We are already seeing many breakthroughs in using APIs with both Facebook and Twitter that will change the landscape of management information systems.