  This is an expository article detailing results concerning large arcs in
finite projective spaces, which attempts to cover the most relevant results on
arcs, simplifying and unifying proofs of known old and more recent theorems.
The article is mostly self-contained and includes a proof of the most general
form of Segre's lemma of tangents and a short proof of the MDS conjecture over
prime fields based on this lemma.
