the relative costs by similar orders of magnitude (see Moore's law). Additionally, the spread of computers through all levels of business and home life has produced a software industry many times larger than it was in the 1970s. Programs are now usually churned out by teams, directed by committees in software development studios (also known as software houses or software factories) where each programmer works on only a part of the whole, on one or more subroutines. Finally, software development tools and approaches often result in changes throughout a program to accommodate each feature, leading to a large-scale inclusion of code which affects the main operation of the software, and is required in order to support functions that themselves may be only rarely used. In particular, the advances in resources available have led to tools which allow easier development of code, again with less priority given to end efficiency. Another cause of bloat is independently competing standards and products, which can create a demand for integration. There are now more operating systems, browsers, protocols, and storage formats than there were before, causing bloat in programs due to interoperability issues. For example, a program that once could only save in text format is now demanded to save in HTML, XML, XLS, CSV, PDF, DOC, and other formats. Niklaus Wirth has summed up the situation in Wirth's law, which states that software speed is decreasing more quickly than hardware speed is increasing. In his 2001 essay Strategy Letter IV: Bloatware and the 80/20 Myth, Joel Spolsky argues that while 80% of the users only use 20% of the features (a variant on the Pareto principle), each one uses different features. Thus, "lite" software editions turn out to be useless for most, as they miss the one or two special features that are present in the "bloated" version. Spolsky sums the article with a quote by Jamie Zawinski referring to the Mozilla Application Suite (which later became SeaMonkey): "Convenient though it would be if it were true, Mozilla is not big because it's full of useless crap. Mozilla is big because your needs are big. Your needs are big because the Internet is big. There are lots of small, lean web browsers out there that, incidentally, do almost nothing useful. [...] But being a shining jewel of perfection was not a goal when we wrote Mozilla." Software bloat may also be a symptom