Here’s a summary of several popular frontend frameworks:

1. React.js: A JavaScript library for building user interfaces, known for its component-based structure and maintained by Facebook.
2. AngularJS: An older version of the Angular framework, providing features for dynamic web applications.
3. Vue.js: A progressive JavaScript framework for creating user interfaces, valued for its simplicity and flexibility.
4. jQuery: A lightweight JavaScript library that simplifies HTML document manipulation and traversal.
5. Bootstrap: A popular front-end framework that offers CSS and JavaScript tools for creating responsive and visually appealing web designs.
6. Ember.js: A JavaScript framework that focuses on creating ambitious web applications with a strong emphasis on convention over configuration.
7. Backbone.js: A lightweight framework that provides the structure for web applications with a minimalistic approach.
8. Semantic-UI: A CSS framework designed for creating beautiful, responsive user interfaces with a strong emphasis on semantic HTML.
9. Foundation: A responsive front-end framework that offers a set of customizable CSS and JavaScript components.
10. Svelte: A relatively new framework for building user interfaces that compiles to highly efficient vanilla JavaScript code.
11. Preact: A fast and lightweight alternative to React, designed for building efficient web applications with a smaller footprint.
12. Tailwind CSS: A utility-first CSS framework that enables rapid development by providing a set of utility classes for styling.

These are the key features and focuses of each framework, and you can explore them further based on your project requirements or interests.