His writings fall into three main categories, each with a very different style and tone.
His "Xeelee Sequence" stories are set in the far future, where human beings are rising to become the second most powerful race in the universe, next to the god-like Xeelee. Character development in these stories take second place to the depiction of advanced theories and ideas, such as the true nature of the Great Attractor, naked singularities and the great battle between Baryonic and Photonic lifeforms. Examples of novels written in this style: Ring, Timelike Infinity.
His present-day Earth stories are much more human, with characters portrayed with greater depth and care. They typically indulge in "if only" whimsy, dreaming about what humanity could achieve in the exploration of space. NASA features prominently, and a great deal of research has obviously been done into its internal structuring and methods. However, these novels have a much darker tone than any of his other stories and do not often portray much hope for humanity as a moral species. Examples of novel written in this style: Voyage, Titan, Moonseed.
His "Evolution" stories are a later development and show an increasing interest in the evolution of humanity. These seem to have their origins in stories of his other writing styles, such as Mammoth and Manifold: Origin. Examples of novels written in this style: Evolution.
Baxter also covers numerous other styles: His Mammoth stories, ostensibly for children, are often of great delight to adults, while The Time Ships (an authorised sequel to The Time Machine) is generally taken to be one of his greatest novels yet.
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