Several programming languages are commonly used for backend web technologies, including:

• JavaScript (with Node.js)

• Python

• Java

• Ruby

• PHP

• Go

• C#

Javascript

JavaScript (with Node.js) JavaScript is a popular language for backend web development because of its flexibility and versatility. Node.js, a JavaScript runtime, allows developers to run JavaScript on the server side, making it a popular choice for building real-time, high-performance, and scalable web applications. One of the main use cases for using JavaScript with Node.js is building real-time applications such as chat applications, online games, and live-streaming platforms

Python

Python is a popular language for backend web development because of its simplicity and ease of use. It is well-suited for building a wide range of web applications, from small scripts to large-scale enterprise systems. One of the main use cases for using Python is building data-driven web applications.

Java

Java is a popular language for backend web development because of its stability and scalability. Java is known for its "write once, run anywhere" philosophy, which means that Java code can be run on any platform that supports a Java Virtual Machine (JVM). This makes it an excellent choice for building large-scale, enterprise-level web applications that need to be deployed on different platforms.

Ruby

Ruby is a popular language for backend web development because of its simplicity and expressiveness. Ruby is often used for building web applications that are easy to maintain and extend. It has a simple and intuitive syntax that makes it easy for developers to read and write code. One of the main use cases for using Ruby is building web applications that need to be built quickly and efficiently

PHP

PHP is used for building web applications that need to be built quickly and efficiently. PHP with Laravel, it's perfect and clean, way different than those old PHP projects where things were all mixed up and buggy. It's easy to find hosting for it and there's Octane too, which gives an excellent performance boost by behaving similarly to Node servers.

Go

Go, also known as Golang, is a popular language for backend web development because of its simplicity, performance, and scalability. Go was designed by Google to be a fast and efficient language for building web applications and networked systems. Go is well-suited for building web applications that need to handle a large number of concurrent connections and handle high traffic.

C# (C-Sharp)

C# can be used to build web applications using the ASP.NET Framework, which is a web development framework developed by Microsoft. ASP.NET provides a rich set of libraries and tools for building web applications, including support for web forms and MVC (Model-View-Controller) patterns. Additionally, C# can also be used to build web APIs, which are a set of endpoints that can be used to access a web application's functionality.

In conclusion, the language chosen depends on the specific use case and personal preference. Each language has its own set of strengths and weaknesses and can be used to build robust, scalable, and efficient backend systems.