To get started, you should have a desktop or laptop running on Windows, Linux, or macOS. Please use the updated Windows 10 or Ubuntu 20.04 long-term support (LTS). Alternatively, use the latest version of macOS (newer than macOS 10.14), such as macOS Catalina.

For your integrated development environment (IDE) to run smoothly, your system should have at least an Intel Core i5 processor along with a minimum of 4 gigabytes (GB) of random-access memory (RAM).

You will need an active internet connection to download and install Qt. As a prerequisite, you should also be familiar with C++ as Qt requires C++ programming knowledge.

Qt is a cross-platform software development framework for desktop, embedded, and mobile platforms. It follows the philosophy of code less, create more, and deploy everywhere. It supports platforms such as Windows, Linux, macOS, VxWorks, QNX, Android, iOS, and so on. The software also supports several microcontroller units (MCUs) from NXP, Renesas, and STMicroelectronics running on bare metal or FreeRTOS.

Qt was born as an attempt to provide a uniform graphical user interface (GUI) with the same look, feel, and functionality across different platforms. Qt accomplishes that by providing a framework to write code once and ensure that it runs on other platforms with minimal or no modifications. It is not a programming language, but rather a framework written in C++. The Qt framework and tools are dual-licensed under open source and commercial licenses.

Qt uses a modular approach to group related functionalities together. Qt Essentials are the foundation of Qt on all platforms. These modules are general and useful for most Qt-based applications. Essential modules are available for open source usage. Examples of Qt Essentials modules are Qt Core, Qt GUI, Qt QML, Qt Widgets, and so on. There are also special-purpose add-on modules that provide specific functionalities and come with certain license obligations. Examples of add-on modules are Qt 3D, Qt Bluetooth, Qt Charts, Qt Data Visualization, and more. As well as this, there are value-added modules such as Qt Automotive Suite, Qt for Device Creation, and Qt for MCUs, among others available under the commercial license.

To find out more about different Qt modules, visit https://doc.qt.io/qt-6/qtmodules.html.

Qt was released for public use in 1995. Since then, there have been many improvements and major changes. Qt 6 is the new major version of Qt. Its main goals are to remain prepared for the requirements coming in 2020 and beyond, remove obsolete modules, and be more maintainable. With this focus, there are architectural changes in Qt 6 that may break some level of backward compatibility with earlier versions.

Some essential modifications in Qt 6 are outlined here:

• Introduction of strong typing
• JavaScript as an optional feature of Qt Modeling Language (QML)
• Removal of QML versioning
• Removal of the duplicate data structures between QObject and QML
• Avoidance of the creation of runtime data structures
• Compilation of QML into efficient C++ and native code
• Support for hiding implementation details
• Better integration of tools

Now that we've covered the basics, let's look at the main reasons for using Qt…

Qt is a modular, cross-platform application development framework. The biggest misunderstanding about Qt is that many people consider it as a GUI framework. However, Qt is much more than a GUI framework. It not only comprises a GUI module, but also a set of modules to make application development faster and easier to scale on various platforms. The biggest benefit of using Qt is its ability to provide portability to various platforms. Here are some advantages of using Qt for developers:

• You can create incredible user experiences for your customers and boost your company brand using Qt.
• Cross-platform development saves both time and money. You can target multiple platforms with the same code base.
• Qt is known for making C++ easy and accessible. With Qt, developers can easily create high-performance, scalable applications with a fluid UI.
• Due to the open source model, the framework is future-proof, along with a great ecosystem.
• It further supports different programming languages and is a very flexible and reliable framework. Consequently, there are great companies such as Adobe, Microsoft, Samsung, AMD, HP, Philips, and MathWorks using Qt for their applications. Many open source projects such as VLC (previously known as VideoLAN Client), Open Broadcaster Software (OBS), and WPS Office (where WPS stands for Writer, Presentation, and Spreadsheets) are also built on Qt.

The core values of Qt are outlined as follows:

• Cross-platform nature
• Highly scalable
• Very easy to use
• Built-in with world-class application programming interfaces (APIs), tools, and documentation
• Maintainable, stable, and compatible
• A large community of users

Whether you are a hobbyist, a student, or working for a company, Qt provides great flexibility to use its modules as per your requirement. Many universities are using Qt as one of their coursework subjects. So, Qt is a great choice for programmers to start building new applications with ready-made features. Let's start by downloading and installing Qt 6 on your machine.