  In this paper, we review observational aspects of three common small-scale
energetic events in the solar transition region (TR), namely: TR explosive
events, ultraviolet bursts and jets. These events are defined in either (both)
spectral or (and) imaging data. The development of multiple instruments capable
of observing the TR has allowed researchers to gain numerous insights into
these phenomena in recent years. These events have provided a proxy to study
how mass and energy are transported between the solar chromosphere and the
corona. As the physical mechanisms responsible for these small-scale events
might be similar to the mechanisms responsible for large-scale phenomena, such
as flares and coronal mass ejections, analysis of these events could also help
our understanding of the solar atmosphere from small to large scales. The
observations of these small-scale energetic events demonstrate that the TR is
extremely dynamic and is a crucial layer in the solar atmosphere between the
chromosphere and the corona.
