Given their low surface brightness, it is hard to determine high-quality spectra of dwarf galaxies outside the Local Group, where it is not possible to study the individual stars. Although several studies exist that use absorption line lengths to study the stellar populations of dwarf galaxies, studies of the Star Formation Histories in these

Extremely faint galaxies (mu_V>27 mag/arcsec^2), have only been discovered in the Local Group. These galaxies are very low in mass (tens of 10^5 Msun) and compact (effective radius <1 kpc). These objects populate the least massive dark matter haloes capable of producing stars, providing us with valuable insights into the nature of star formation at

How large-scale structures formed in the early universe is a key cosmological question with few answers from empirical evidence. Unveiling galaxy clusters and their high-z progenitors (i.e., protoclusters) is essential to picture galaxy evolution drawn by the hierarchical formation scenario. However, unveiling these early structures at high