This work analyses the enterprise architectures questions. Enterprise architecture is relatively familiar in the field of informatics today. It covers discipline of modeling and planning development of information technology, especially in wide organizations. Enterprise architecture is an important branch under the conditions that system complexity exceeds brain capacities of workers. The first part deals with analysis of enterprise architecture, primarily structure, content and relationship to whole enterprise. The most important part of this section is a characterization of enterprise architecture frameworks that facilitate entire process of formation. The second part deals with introduction of three essential architecture frameworks: Zachman, TOGAF and FEAF. Subsequently FEAF is compared with two previous frameworks. The conclusion of this work contains short comparison of features and contents all three mentioned enterprise architecture frameworks.