This introductory text was spoken at the beginning of many Star Trek television episodes and films, from 1966 onward.
Space: The final frontier
These are the voyages of the Starship, Enterprise
Its 5 year mission
To explore strange new worlds
To seek out new life and new civilizations
To boldly go where no man has gone before
This line reinvigorated the last-lasting debate over split infinitives. These are infinitives that have an adverb between 'to' and the verb. Those grammarians who still cared about this in the 1960s complained that 'to boldly go' should have been 'to go boldly'. The debate had been simmering on and off for the best part of a century. As early as 1897, Academy magazine suggested that an insistence that split infinitives were incorrect was somewhat pedantic:
"Are our critics aware that Byron is the father of their split infinitive? 'To slowly trace', says the noble poet, 'the forest's shady scene'."
Most authorities now accept Star Trek into the grammatical fold and no longer care, or at least rarely publicly complain, about 'to boldly go'.