Micro-work internet services allocate small, standardized tasks of data generation and annotation to crowds of providers. The outputs are mainly used to produce artificial intelligence solutions. It is an exemplary instance of the ?platformization? of the economy, and of the transformations of labour that digital technologies bring about. To uncover the conditions under which micro-work is performed, and its broader societal implications, we conducted an extensive empirical study in France. In this paper, we use the data collected to present the socio-economic backgrounds of the people who engage in micro-work, their motivations and needs, and their everyday practices. We show that, while the micro-working population is very diverse, a significant portion (including working women with children and with higher education degrees) face pressing financial needs and rely on this activity to make ends meet. Micro-workers are also exposed to distinctive psycho-social risks, without adequate protection and with only limited opportunities to voice issues or seek advice. Especially as the current boom of artificial intelligence raises demand for their services, their working conditions call for attention from policy-makers, unions, and the general public. This article is a summarized version of the report ?Le Micro-travail en France. Derrière l?automatisation de nouvelles précarités au travail?»