Final answer:
Chrome extensions are written using JavaScript, HTML, and CSS. JavaScript provides functionality, HTML structures the user interface, and CSS styles it.
Step-by-step explanation:
The language primarily used for writing Chrome extensions is JavaScript. However, developing a Chrome extension often involves a combination of web development technologies, including HTML and CSS for structuring and styling the extension's user interface, respectively. These are the core technologies of the web and form the basis of most web content today. To create a Chrome extension, developers typically put together a manifest file (in JSON format), HTML files for any user interfaces, JavaScript for the extension's functionality, and optional CSS files for styling. It's also possible to include other web-related technologies, such as various JavaScript frameworks or libraries, to enhance the functionality or appearance of the extension. An example of a Chrome extension might be a popup that provides a feature to the user every time they open a new tab, and this could be coded using a combination of HTML, CSS, and JavaScript.
HTML: It is a markup language used to define the structure and content of a webpage. In the case of Chrome extensions, HTML is used to define the user interface elements such as buttons, text boxes, and images.
CSS: It is a styling language used to control the layout and appearance of HTML elements. CSS is used to design the visual aspects of the extension, such as colors, fonts, and spacing.
JavaScript: It is a scripting language used to add dynamic behavior to webpages. In the context of Chrome extensions, JavaScript is used to implement the functionality of the extension, handle user interactions, and communicate with external resources.