A company, corporation, or firm — an organization engaged in business activities.
明日から新しい会社で働き始めます。
I'll start working at a new company from tomorrow.
その会社は国内外に支社を持っている。
That company has branches both domestically and abroad.
彼は中小企業を経営している。
He runs a small-to-medium-sized company.
One's workplace — used to refer to the company or place where one works.
今日は会社で会議があるので遅くなります。
I have a meeting at the office today, so I'll be late.
会社の同僚と飲みに行った。
I went drinking with coworkers from my company.