The term "techno-mathematical literacies" captures two important aspects of the ways that mathematics surfaces in workplace situations. First, that the knowledge involved is much closer to a literacy than a skill; and second, that it is almost always represented as knowledge mediated by a computer.
Why literacy? A literate person is someone who is competent in using language, both written and verbal, across different contexts and working with different rules and conventions. This core idea of literacy is crucial for mathematics as well: individuals need to be able to understand and use mathematics as a language that increasingly pervades the workplace through IT-based control and administration systems as much as conventional literacy (reading and writing) has pervaded working life for the last century.
Why techno? This literacy is expressed through technological artefacts. It is the particular nature of mathematical skills in workplaces, where IT is pervasive, which distinguishes the kind of knowledge involved: a computer graph, for example, has properties different to a pencil-and-paper graph, and a column of numbers on a spreadsheet can be manipulated as an object in ways in which it's paper-and-pencil "equivalent" cannot.
The idea of techno-mathematical literacies is related to other approaches that have taken a general perspective of the education process as it is experienced by young people - cf. (OECD, 2003) and the Quantitative Literacy movement in the USA (e.g., Steen, 1997). For example, the OECD's Programme of International Student Assessment (PISA) defines it as follows:
In workplaces, as much as in the broader culture, this kind of necessary mathematical literacy is supplemented by the ubiquity of the computer: Noss (1998) and diSessa (2000) offer extensive discussion of the idea of mathematical literacy, showing how the new forms of computational technology that are used for doing mathematics are connected with new ‘mathematical literacies'. The most complete description and examples techno-mathematical literacies is to be found in Hoyles, Noss, Kent and Bakker (2010): for a review, see Gainsburg, 2011).