# Chapter 1: Prerequisite Language Level

This chapter presents two languages required for understanding the content in the other chapters: the part of UML for creating class diagrams and Object Constraints Language (OCL). The presentation of the full UML 2.0 is given in Chapter 5.

## Lecture: OCL 2.0

This lecture covers Object Constraints Language 2.0.

## Lecture: Assertions, Constraints, and OCL

This lecture explains the usage of OCL in specifying assertions and constraints in the context of design by contract.

## Lecture: UML and Object Orientation. The Fundamentals

This lecture presents the basic principles of object orientation and their application in UML.