announcement vs program

announcement and program both are nouns.

Word	Noun	Adjective	Verb	Adverb
announcement	Yes	No	No	No
program	Yes	No	Yes	No

As nouns, program is a hyponym of announcement; that is, program is a word with a more specific, narrower meaning than announcement:

announcement: a public statement containing information about an event that has happened or is going to happen
program: an announcement of the events that will occur as part of a theatrical or sporting event

Other hyponyms of announcement include advisory, banns, handout, press release, release, notice, programme, wanted notice, wanted poster.

announcement (noun)	program (noun)
a public statement containing information about an event that has happened or is going to happen	a performance (or series of performances) at a public presentation
a formal public statement	a series of steps to be carried out or goals to be accomplished
	a system of projects or services intended to meet a public need
	an announcement of the events that will occur as part of a theatrical or sporting event
	a radio or television show
	(computer science) a sequence of instructions that a computer can interpret and execute
	a document stating the aims and principles of a political party
	an integrated course of academic studies

announcement (verb)	program (verb)
	arrange a program of or for
	write a computer program