I am currently using two operating systems: Linux and Windows. Now, I am interested in learning PHP and I am trying to figure out whether it is better to do this on Windows using Denwer or on Linux with LAMP. Additionally, I am a bit confused about what LAMP actually is.
Is it a server that can be accessed over the Internet to host a website, or can it operate locally? I would appreciate a detailed explanation of this. Thank you.

Let's clarify what LAMP is. LAMP stands for Linux, Apache, MySQL, and PHP/Perl/Python. It's a software stack that provides a suitable environment for developing and running dynamic web applications. Now, to address your confusion, LAMP is not a server in itself; rather, it's a set of open-source software that together can be used to host websites. This software stack can certainly operate locally on your machine for development purposes, but it's also commonly used on servers to host websites that are accessible over the Internet.

In terms of which environment would be better for learning PHP, it often comes down to personal preference. If you're more comfortable with Windows, using Denwer can provide a familiar environment for getting started with PHP development. On the other hand, if you're interested in working with open-source technologies and want to immerse yourself in a system that closely mirrors what many web servers run on, then setting up LAMP on a Linux machine could offer a more authentic experience.
Both options have their own advantages and can help you gain valuable skills. If you have specific projects in mind or future career goals, those might also influence your decision.

I'd like to introduce you to DENWER, a comprehensive web developer kit designed by Dmitry Koterov and his team. It offers various builds including PHP, Apache (Nginx), MySQL, and phpMyAdmin. Despite being an old tool in the market, DENWER is not just alive but actively maintained and developed.

Originally created for Windows users, especially novices, DENWER has proven to be so convenient that even professionals continue to use it. Personally, I have reservations about Windows and DENWER, but as a starting point, it's undeniably useful. I highly recommend exploring Dmitry Koterov's book on PHP, which covers DENWER and its usage, providing valuable insights. The author's dоcumentation itself is a valuable resource.

After a month or two of using DENWER, I strongly advise stepping out of your comfort zone, embracing Ubuntu, and learning how to set up everything from scratch.

LAMP is an acronym representing a specific technology stack - Linux, Apache, MySQL, and PHP. It's essential to understand that LAMP is not a server, service, or host, but rather a combination of these technologies for web development. Similarly, in Windows, the equivalent stack is referred to as WAMP.
It's important to note that using Denwer may not be the most beneficial approach. If you prefer working in Windows, it's advisable to install Apache, MySQL, and PHP individually. This hands-on approach will provide a better understanding of the system. Otherwise, it's like being taught to drive a car without being told about refueling – not an ideal situation.

Denwer is a bit of a hacky Windows solution, more like a quick-and-dirty playground. LAMP on Linux is the real deal — it's a full-fledged server environment that you can run locally or expose to the Internet if you configure it right.
LAMP is not some mysterious remote server; it's your local LAMP stack mimicking production. If you want to get serious with PHP, ditch Windows and embrace Linux.