arXiv is a repository of electronic preprints approved for posting after moderation, but not full peer review. It consists of scientific papers in the fields of mathematics, physics, astronomy, electrical engineering, computer science, quantitative biology, statistics, mathematical finance and economics, which can be accessed online.

Many machine learning articles will be posted on arXiv before publication. In theoretical computer science and machine learning, over 60% of published papers have arXiv e-prints (Sutton et al. 2017).

Multimodal machine learning aims to build models that can process and relate information from multiple modalities (including linguistic, acoustic and visual signals). Multimodal machine learning enables a wide range of applications: from audio-visual speech recognition to image captioning (Baltrusaitis et al., 2017).