Productive prefix forming superlatives and emphatic expressions. Also used as a na-adjective in phrases like 最の～. Common in compounds such as 最高, 最低, 最新, 最悪.
This is the latest technology.
taru-adjective, adverb taking the 'to' particle
prime; conspicuous; most notable
Literary and somewhat archaic use as a taru-adjective or adverb with と. Most often encountered in the fixed expression 最たる (prime, foremost).
See also: 最たる
He got the best grades in the class.
He is one of the foremost writers of our time.
That incident can be cited as a prime example.
最 forms standard superlative compounds like 最高 and 最新, whereas 超 is a casual, slangy intensifying prefix (超すごい) that emphasizes degree rather than strictly meaning 'most'.
最 is a bound prefix that must attach to another word to form a compound (最高, 最新), while 最も is a free-standing adverb meaning 'most' that modifies an adjective or verb on its own (最も高い山).
再 (さい, 're-/again') and 最 (さい, 'most') share the same reading but have completely unrelated meanings, so learners can mix up which kanji to write.
The kanji 最 is a Sino-Japanese morpheme meaning 'most' or 'extreme'. It is used productively as a prefix in modern Japanese.
optimal; best; most suitable
in the middle of; in the midst of; at the height of
fastest; quickest
minimum; lowest limit · at the very least; at minimum
one's last moment; one's death; one's end
smallest; least; minimum; minimal
most numerous; largest number of
cutting edge; forefront; state of the art · tip; extreme end
maximum; greatest possible · to the fullest; as much as possible
shortest; minimum
best; top; most outstanding
Supreme Court
the very best; utmost
minimum; minimum necessary; minimal · at a minimum; at least
longest; maximum length; maximum duration · oldest; most senior
highest peak; highest mountain · pinnacle; greatest authority; most prominent person
last place; lowest rank; bottom · least significant (bit); lowest order
front line; forefront
the best; ideal; optimum
highest; top · best; finest; supreme
the oldest; the earliest