1. 1. Angular CLI: Angular CLI is a command line interface that provides a powerful set of tools and commands for developing Angular applications. It allows for efficient code generation, building, testing, and deployment of Angular projects. Angular CLI uses Angular's preferred file structure and provides a wide range of features and functionalities, including hot module replacement, code scaffolding, and project configuration.

2. 2. Vue CLI: Vue CLI is a command line interface for Vue.js applications, providing a streamlined development experience. It offers a collection of build tools, plugins, and presets to help developers create Vue applications in a flexible and efficient way. Vue CLI allows developers to scaffold projects, manage dependencies, and configure different aspects of the development environment.

3. 3. Build Tools and Project Structure: One of the key differences between Angular CLI and Vue CLI is the build tools and project structure they use. Angular CLI utilizes Webpack as its default build tool and enforces a specific file structure and naming conventions. On the other hand, Vue CLI provides more flexibility in terms of build tools, allowing developers to choose between Webpack, Rollup, or Browserify. It also allows for a more relaxed project structure, allowing developers to organize their code in a way that suits their preferences.

4. 4. Programming Style: Another difference lies in the programming style favored by each CLI. Angular CLI promotes a more opinionated and structured approach to development, using TypeScript as the default programming language. It encourages the use of Angular's powerful features, such as decorators and dependency injection. Vue CLI, on the other hand, is more flexible in terms of programming style and supports both JavaScript and TypeScript. It allows developers to choose between various libraries and tools to enhance their Vue applications.

5. 5. Ecosystem and Community Support: Both Angular CLI and Vue CLI have active and supportive communities, but the ecosystems surrounding them are different. Angular CLI benefits from the rich ecosystem of Angular, which offers a wide range of libraries, tools, and resources. It has a large community of developers and comprehensive documentation. Vue CLI, while gaining popularity, has a smaller ecosystem compared to Angular. However, it still has a supportive community and offers a growing number of plugins and tools for Vue.js development.

6. 6. Learning Curve and Complexity: Due to its opinionated nature and more advanced concepts, Angular CLI generally has a steeper learning curve and can be perceived as more complex for beginners. It requires a solid understanding of Angular's concepts and architecture. However, once mastered, it provides a powerful and feature-rich development experience. Vue CLI, on the other hand, is known for its simplicity and ease of learning. It has a gentle learning curve, making it more accessible for beginners or developers looking for a lightweight framework.

In summary, the key differences between Angular CLI and Vue CLI lie in their build tools and project structure, programming style, ecosystem and community support, and the learning curve and complexity they present. Angular CLI is more opinionated, promotes TypeScript, and has a larger ecosystem, while Vue CLI offers more flexibility, supports JavaScript and TypeScript, and has a simpler learning curve.