Modelio is a robust program for Windows that offers an accessible UML environment supported by an extensive collection of models and diagrams. Notably, the only prerequisite is the presence of a Java installation.

General notes

Deployment is quite straightforward. All you need to do is double click the setup file and follow the instructions provided on the screen by the wizard. You can also save the solution on a portable storage device like a USB drive.

The UI is both user friendly and professional. It is possible to jump right into your project, whether it is Java related or not, and populate it with a wide array of stereotypes. These include class diagrams, data flows, connectors, extension points, events, interactions, and more.

Advanced configuration

Similar to Argouml, the utility allows you to modify various elements related to UML, audit, notes, and constraints. You can configure the settings encompassing general and storage information, work models, libraries, URLs, and so on.

What is more, there are instruments for catalog management, namely modules and macros. There is an option to customize diagram styles. Users can also navigate and explore outlines, audit data, elements, scripts, symbols, etc.

Features

free to download and use;
compatible with modern Windows versions;
enables you to visualize designs of systems;
the program requires a Java installation;
you can modify various UML elements.