The first, until the mid-1990s, was a kind of geek Eden, characterised by bold experimentation and a shared sense that start-ups like Netscape and Yahoo! would truly change everything.
The second, by contrast, saw the online world become the playground of venture capitalists and lawyers, driven by the view that dotcoms were virtually a licence to print money.
An emblematic moment during the shift between the two phases took place on 12 December 1995. It was then that Microsoft officially "got" the Internet. Until Bill Gates' famous speech on Pearl Harbour Day, Microsoft had been at best tepid about the Net, not least because it was based on pre-existing, open standards.
After the Pearl Harbour Day speech, conquering the Internet became the company's number one priority. This was manifested most clearly in its relentless and highly-successful moves to boost the market share of Internet Explorer, at that stage a feeble competitor to Netscape Navigator.
It was largely Microsoft's over-zealous efforts to promote its browser that provoked the US Department of Justice anti-trust lawsuit that has been one of the other defining features of the later dotcom era.
The latest, and probably last, instalment of this dispiriting saga has recently appeared in the form of a proposed final judgment agreed by Microsoft and the US government (www.usdoj. gov/atr/cases/f9400/9462. htm). Although this has yet to be approved by the courts, and has already been rejected by some of the US states that were party to the original lawsuit, it seems probable that it or something very similar will form the basis of the final settlement.
The main reason why there is unlikely to be much further movement is that the settlement document makes it clear that the Department of Justice, operating under a new and very different US administration from the one that brought the anti-trust action, has thrown in the towel.
The US government's capitulation is most clearly seen from the fact that there are no immediate penalties for breaking the new agreement, even though Microsoft has been found guilty of anti-trust practices.
Instead, the US government is granted "the authority to seek such orders as are necessary from the court to enforce this final judgment" - in other words, Microsoft graciously allows the Department of Justice to go back to the courts.
Moreover, another paragraph stipulates that "in any enforcement proceeding in which the court has found that Microsoft has engaged in a pattern of knowing, wilful and systematic violations," - very stringent conditions, be it noted - "the United States may apply to the court for a one-time extension of the final judgment of up to two years" - over and above the initial five years - "together with other such relief as the court may deem appropriate."
This is a "one-time extension" of an already nearly toothless agreement, after which Microsoft can presumably do what it likes as far as the Department of Justice is concerned.
There is one other highly significant exemption that Microsoft has shrewdly placed among the various mild concessions it has otherwise granted (mostly promising not to do things that it has already done in the past, and which are in any case largely irrelevant now):
"No provision of this final judgment shall:
1. Require Microsoft to document, disclose or license to third parties:
(a) portions of APIs or documentation or portions or layers of Communications Protocols the disclosure of which would compromise the security of anti-piracy, anti-virus, software licensing, digital rights management, encryption or authentication systems."
That is, whatever else, Microsoft is under no obligation to share information about precisely those markets where most growth is likely in the future - secure e-commerce in its broadest sense and digital rights management.