Handlebars.js vs Underscore: What are the differences?

Introduction

Handlebars.js and Underscore are both popular JavaScript libraries commonly used in web development. While they share some similarities, there are several key differences between the two that developers should be aware of. This Markdown code provides a brief comparison of Handlebars.js and Underscore, highlighting their main distinctions.

1. Syntax and Templating: Handlebars.js is primarily a templating engine that allows for dynamic content rendering. It provides a simple and intuitive syntax, utilizing custom delimiters (such as {{}}) for injecting data into HTML templates. On the other hand, Underscore focuses more on manipulating and iterating over data with a functional programming approach, offering utilities like map, filter, and reduce functions.

2. Template Rendering: Handlebars.js operates by taking a template and binding it to data, which can then be rendered as HTML. It excels at rendering complex templates with custom logic and partials, making it a popular choice for rendering dynamic content. In contrast, Underscore does not have built-in templating capabilities and is mainly used for data manipulation and transformation.

3. Data Binding: Handlebars.js provides data binding functionality, where changes in the data are automatically reflected in the rendered views. This enables developers to create reactive interfaces without manually updating the DOM. Underscore, however, does not have built-in data binding capabilities, requiring developers to handle data updates manually.

4. Compatibility: Handlebars.js can be used in both client-side and server-side environments, making it versatile for various development scenarios. It can be integrated with frameworks like Ember.js for enhanced functionality. Meanwhile, Underscore is primarily designed for client-side JavaScript and is commonly used as a utility library in conjunction with other frameworks or libraries.

5. Dependencies: Handlebars.js has no external dependencies and can be used as a standalone library. It has its own template engine and does not rely on other external JavaScript libraries. On the other hand, Underscore has no dependencies on other libraries either and can be used independently.

6. Size: Handlebars.js is relatively larger in size compared to Underscore. The minified version of Handlebars.js is around 16 KB, while Underscore's minified version is only about 5 KB. This size difference can be a factor when considering page load times and network bandwidth.

In summary, Handlebars.js specializes in templating and data binding, offering an intuitive syntax for rendering dynamic content, while Underscore focuses more on data manipulation and functional programming. Both libraries have their own strengths and use cases, depend on the specific requirements of the project.