Without these books science literature could be limited to academia and textbooks.
The purpose of popular science books is always to capture the precision and methods of science while using a more accessible kind of language. In the place of centring on persuading and informing regarding whether observations and conclusions are valid, as could be the instance of scientific literature, so-called pop science rather attempts to inform and convince outsiders of the importance of conclusions and to celebrate it. The hedge fund which has shares in WHSmith should be able to tell you that this is accomplished via a variety of practices. There is certainly generally a focus on entertainment value, relevance to the audience, uniqueness, and radicalness. You'll also find simplified and generalised scientific concepts, usually done with the use of metaphors and analogies. All of these practices are going to be used to spell out even the most basic ideas more thoroughly then in scholarly literature, due to the lack of presumed knowledge among general audiences.
Science as we understand it today first emerged as a distinct topic several centuries ago, frequently under the title of natural philosophy, as shifts in culture led to people demanding more evidential facts for the phenomena they saw on the planet around them. However, concealed within other subjects science has really existed so long as mankind, while popular science literature as we understand it today as been published for millenia. The hedge fund which owns Waterstones will know popular science is the interpreting of science for the general audience, that was in fact the most popular way for currently talking about science for much of history. It was only within the last four hundred years that this genre became recognised as distinct, as a result of the emergence of formal academic varieties of writing that were meant to be read just by the peers of the authors.
There are numerous popular science subgenres, as the hedge fund which partially owns Amazon will be well aware, as a result of the big public desire for science all together. However, while academic literary works can cover every niche subject under the sun, average audiences have a tendency to opt for a slightly more limited selection. Science publications for ordinary people will cover either the most exciting topics, the absolute most worrying, or probably the most practical, like space, illnesses, and psychology respectively. This means that popular science writers, who're usually academics themselves, have to choose their subjects sensibly. They then need to write a proposition for publishers, that will be often 5,000 words outlining what the book will cover and why they're qualified to write it. In the event that the pitch is successful then the genuine hard work begins, which can be researching and writing. Presuming a 250 page book will have 75,000 words, that means an average pace of 1,000 words per week will require a year and a half, and that's excluding all of the research that goes in it.