1. A computer-implemented method for providing a unified catalog, the method comprising: sending, by a processor, data retrieval format requirements to two or more underlying catalog systems; receiving, by a processor, an application programming interface from the two or more underlying catalog systems; importing, by a processor, catalog data from the two or more underlying catalog systems using the application programming interface, wherein the two or more underlying catalog systems are disparate and independent catalog systems associated with a single entity; identifying, by a processor, items from the catalog data; determining, by a processor, a unique identifier associated with each of the items from the catalog data, wherein the unique identifier comprises a Stock Keeping Unit (SKU); identifying, by a processor, duplicate items from multiple catalog systems of the two or more underlying catalog systems based on the unique identifier; wherein identifying duplicate items comprises matching an SKU of a first duplicate item of a first underlying catalog system with an SKU of a second duplicate item of a second underlying catalog system, wherein the first underlying catalog system did meet its service level agreement deadlines within a previous predetermined period of time, and wherein the second underlying catalog system did not meet its service level agreement deadlines within the previous predetermined period of time; determining, by a processor, a preferred catalog system between the first underlying catalog system and the second underlying catalog system, wherein determining the preferred catalog system comprises determining that the first underlying catalog system did meet its service level agreement deadlines within the previous predetermined period of time and that the second underlying catalog system did not meet its service level agreement deadlines within the previous predetermined period of time; identifying, by a processor, between the first duplicate item and the second duplicate item, a preferred item associated with the preferred catalog system; retaining, by a processor, in the unified catalog system, the preferred item; removing, by a processor, all other duplicate items from the unified catalog; identifying, an administrator, wherein the administrator is granted permission to make modifications to the imported catalog data; receiving, by a processor, a request from the administrator to modify at least one of item descriptions, item names, product categories, and item identifiers associated with the identified items; upon receiving the request to modify from the administrator, modifying, by a processor, at least one item information of item descriptions, item names, product categories, and item identifiers associated with the identified items; providing, by a processor, a unified user interface to a user for browsing the items, wherein the user interface dynamically displays the modified at least one item information to the user; receiving, by a processor, a request for at least one item selected by the user from the items; and sending, by a processor, an order for the at least one selected item to the preferred catalog system.