There are three major Web development platforms, all of which have advantages and disadvantages which can impact which platform is best suited for the user's application: Microsoft's ASP.NET/IIS/Windows Server, Linux/Apache/MySQL/PHP (most often called LAMP), and Sun Java J2EE.x. When the term ASP is used in this particular context, it is referring to ASP.NET and not ASP, which is a similar but entirely different product.
J2EE generally requires high-power, read expensive, servers and it is not routinely implemented in most shared or dedicated hosting environments. It is, however, a viable alternative to either ASP.NET or LAMP implementations.
ASP and LAMP have a long shared history of competition as the foremost of the web development suites, dating back to the early 2000s. Their fans are legion and frequently at odds with each other. Any gathering of programmers and coders is reminiscent of the old Miller Lite TV commercials, where one side shouts "Tastes great!" and the other responds with "Less filling!"
Just as in the commercials, one side is not really superior to the other, although even that statement is likely to spark a heated debate amongst the "true believers."
ASP.NET and LAMP comparisons
As a general rule, ASP.NET is the choice for any Windows or Microsoft-savvy coder. The development tools are similar to every other MS application and the learning curve is relatively short. Drag and drop WYSIWYG and a plethora of computer languages make it the obvious choice, especially if money is not an option.
Where LAMP is open source and there are no licensing fees, the Microsoft web development tools do have licensing fees, although the IIS and .NET technologies are routinely bundled with Microsoft Server and Windows Professional operating systems.
Installation of either ASP.NET or LAMP is fairly routine, with some expectation of the usual tweaks to enable the development tools to operate at optimal efficiency. Microsoft uses standard wizards, where LAMP uses a series of dialogs for installation at both the server and client sides, assuming the client is a coder or programmer.
There is little or no client-side software that is not routinely in place for standard users as the major browsers are capable of interpreting and displaying the web content.
Advantages of either LAMP or ASP.NET
One significant advantage that Apache/MySQL/PHP (AMP) has is that it can be implemented on virtually any host, regardless of hardware or operating system. PHP hosting can run under Windows (WAMP), Linux/Unix (LAMP), Apple Mac (MAMP), Sun/Solaris (SAMP) and others. ASP.NET is run under Windows, or in some cases, can run under a virtual machine or framework in some other operating systems.
The obvious advantage of ASP hosting is language flexibility, error handling and code-behind structures that allow for the coder to work on a processing module without necessarily impacting the user's display or content. ASP enforces a more structured coding environment than LAMP, although the coder/programmer is ultimately responsible for any web development design, regardless of the tools used to build the site.
The bottom line is there is no supremely superior web development environment. All three platforms have great features and are less work than a complete build of a web presence without a development suite. All are superior e-commerce platforms, with large and dedicated user groups for support.
Deciding which one is the best choice for any specific application is entirely dependent on budget, programmer resources, and the web hosting options available. Generally, if the server is Windows/IIS-based, the only choice is ASP.NET, unless a WAMP installation is a possibility. Conversely, if the server is mot Windows-based, then AMP is the only practical choice.