ということ（だ） details
Examples
the fact that; the thing that — packages a whole clause as the content the rest of the sentence talks about
彼が試験に落ちたということが、まだ信じられない。
kare ga shiken ni ochita to iu koto ga, mada shinjirarenai.
I still can't believe that he failed the exam. neutral
明日、休みだっていうこと、聞いた？
ashita, yasumi datte iu koto, kiita?
Did you hear that tomorrow's a day off? casual
I hear that; that means — closes a sentence relaying a report, or drawing a conclusion from what was just said
つまり、今日の会議は中止ってことだね。
tsumari, kyou no kaigi wa chuushitte koto da ne.
So that means today's meeting is canceled, huh. casual
案内によると、来月から新しい制度が始まるということだ。
annai ni yoru to, raigetsu kara atarashii seido ga hajimaru to iu koto da.
According to the notice, a new system will start from next month. neutral
今回の調査結果から、現行の方法では不十分だということでございます。
konkai no chousa kekka kara, genkou no houhou de wa fujuubun da to iu koto de gozaimasu.
From this survey's results, it means that the current method is insufficient. formal
Formation
plain clause + ということ（だ）attaches to plain clause
Notes
with だ, it relays a report or draws a conclusion (usage 2). だ often
clips to って in speech, and can drop entirely before ってこと.
Related patterns
Similar
という packages a clause under any naming or content noun (話・うわさ・意味) and stays open-ended, while ということ narrows the head to こと specifically, and closed with だ it reads as a source relayed or a conclusion drawn — a step という alone doesn't reliably take.
ということだ INFLECTS through a real past tail (ということだった — see this entry's own pattern_forms), something hearsay そうだ can never do (no ×そうだった); ということだ also skews toward written reports and formal announcements, where そうだ stays comfortably conversational.
Lookalikes
One こと apart in the wrong place to skim past — ということだ closes a REPORT or conclusion (中止[ちゅうし]ということだ "that means it's canceled"), while ことだ is a bare advisory imperative built straight on the verb (早[はや]く行[い]くことだ "you'd better go soon") — dropping the leading という changes what kind of sentence you're even in.