  The contribution provides a detailed exploration of the online platform
Perusall as an advanced social annotation technology in teaching and learning
STEM disciplines. This exploration is based on the authors' insights and
experiences from three years of implementing Perusall at P.J. \v{S}af\'arik
University in Ko\v{s}ice, Slovakia. While the concept of social annotation
technology and its educational applications are not novel, Perusall's advanced
features, including AI and data science reports, enable its use in both
synchronous and asynchronous blended and flipped learning environments. In this
context, Perusall serves as a digital tool for collecting formative data,
monitoring student progress, and identifying areas of difficulty. This
assessment data can be effectively utilized in preparing and personalizing
subsequent face-to-face group interactions, thereby enhancing and improving the
learning experience. From a pedagogical viewpoint, Perusall's role was
particularly significant during the Covid-19 pandemic, enabling effective,
continuous, and engaging learning amidst social distancing and physical
restrictions. Today, Perusall has become a key tool in blended learning,
facilitating higher-order cognitive processes during the educational process
and, with its multifaceted applications, serves as a modern catalyst in
redefining educational experiences and outcomes.
