The stellar Initial Mass Function (IMF) suggests that stars with sub-solar mass form in very large numbers.
Most attractive places for catching low-mass star formation in the act are young stellar
clusters and associations, still (half-)embedded in star-forming regions. The low-mass stars
in such regions are still in their pre--main-sequence (PMS) evolutionary phase,
i.e., they have not started their lives on the main-sequence yet. The peculiar nature
of these objects and the contamination
of their samples by the fore- and background evolved populations of the Galactic disk
impose demanding observational techniques, such as X-ray surveying and optical spectroscopy
of large samples for the detection of complete
numbers of PMS stars in the Milky Way. The Magellanic Clouds, the metal-poor companion
galaxies to our own, demonstrate an exceptional star formation activity. The low extinction and
stellar field contamination in star-forming regions of these galaxies imply a more
efficient detection of low-mass PMS stars than in the Milky Way, but their distance
from us make the application of the above techniques unfeasible.
Nonetheless, imaging with the Hubble Space Telescope within
the last five years yield the discovery of solar and sub-solar
PMS stars in the Magellanic Clouds from photometry alone. Unprecedented numbers of such objects are identified
as the low-mass stellar content of star-forming regions in these galaxies, changing completely
our picture of young stellar systems outside the Milky Way, and extending
the extragalactic stellar IMF below the persisting threshold of a few solar
masses. This review presents the recent developments in the investigation of the PMS stellar
content of the Magellanic Clouds, with special focus on the limitations by single-epoch
photometry that can only be circumvented by the detailed study of the observable behavior
of these stars in the color-magnitude diagram. The achieved characterization of the low-mass PMS stars
in the Magellanic Clouds allowed thus a more comprehensive understanding
of the star formation process in our neighboring galaxies.