<p>From wikipedia's entry on I-banking: "Investment banks will typically be concerned with several business units, including Corporate Finance (concerned with managing the finances of corporations, including mergers, acquisitions and disposals), often called the Investment Banking Division of the firm."</p>
<p>From careers-in-finance.com: "Sometimes jobs in corporate finance are referred to as investment banking positions. When you hear phrases such as IBD or IBK people are referring to corporate finance."</p>
<p>From Indiana University's Undergraduate Finance Club Site: "The investment banking side primarily deals with corporate finance and all types of transactions pertaining to it."</p>