Formal equivalent of 今日 (きょう). Used in announcements, business, news, and polite speech. Can function as a noun or adverb.
Thank you for coming today.
本日の会議は午後3時からです。
Today's meeting is from 3 p.m.
We are closed for business today.
This sale is today only.
I will reply by the end of today.
As of today, we are ending our business operations.