 Men and women who make maps have always had a vitally important job to do. In past centuries, the accuracy of hand-drawn charts showing shipping lanes and underwater hazards meant the difference between a safe passage and a wrecked vessel with significant loss of life.  Today, cartographers working in the oil and gas industry no longer work at the drawing board. Instead, they use sophisticated software to create maps showing both the surface and sub-surface of the seas around the UK.  What they produce helps determine the location of oil and gas platforms with pinpoint accuracy, or indicates where exploration teams should start drilling for new reservoirs of fossil fuels.  With so much information available, selecting what to include in a nautical chart has become a skill in itself. Map-makers are now tasked with interpreting data and survey information, and deciding what is relevant and what is not.  Peter Jones, head of profession for the Mapping and Charting Group at the United Kingdom Hydrographic Office (UKHO), says: "You still need to bring human skills to bear. The old adage that what you leave out is as important as what you put in is even more critical these days. We've gone from a data-poor environment to the other extreme - we've got too much information now."  "What was once referred to as marine cartography would be defined today as geographic information systems (GIS)," adds Peter Doheny, GIS manager in the Energy Development Unit at the Department of Energy and Climate Change (DECC). "GIS is a digital mapping system that links maps to data, allowing both the production of traditional maps and spatial data analysis."  Remote sensing and survey techniques provide a wealth of information that the cartographer has to analyse and prioritise. "Cartography offshore doesn't just include map-making, but also covers a multitude of other skills, from understanding how the survey sensors acquire information about the sea bed, and interpreting information and bringing all the survey data together, to understanding the different ways information can be projected onto maps," says Jonathan Everest, deliverables surveyor for marine solutions firm Offshore Marine Management.  "The positioning of offshore facilities needs to be as accurate as possible, to within four inches. Inaccurate positioning of structures on the sea bed could result in having to re-engineer newly installed pipelines. Whether it is the position of a cable, pipeline, wreck or sea-bed feature, without maps detailing this information, accidents would occur."  a background in GIS is a distinct advantage for aspiring map-makers, and today, according to Jones, most recruits are graduates. "The typical disciplines are GIS, geography, geology and environmental sciences. Cartography as a branch of science is not widely available in UK educational institutions. It's not seen as sexy enough."  Everest studied Marine Geography at Cardiff University in the Nineties. He says, "It wasn't specific to what I do now, but it gave me a broad understanding of the marine environment and how we interact with the oceans."  Recent graduate Sam Gillchrest, 22, began working at the UKHO nine months ago, as a trainee cartographer. He will soon finish an 18-week in-house training course that will qualify him to produce his own charts. "I have a marine background and was drawn to the area because I'm an RNLI lifeboat navigator," says Gillchrest, who studied geography, GIS and remote sensing at the University  