Standard term for one's own husband when speaking to others. Within the family, other terms like あなた or パパ are more common.
See also: 良人 (りょうじん)
My husband is an office worker.
I went shopping with my husband.
She divorced her husband last year.
She was widowed at a young age when her husband died first.
She always supports her husband.
My friend is troubled because her husband cheated on her.
夫 is the standard, neutral word for 'husband' used in formal writing, whereas 亭主 is colloquial and often implies he rules the household.
夫 is the standard modern word for one's husband, whereas 宅 in that sense is rare, old-fashioned, and used mainly by wives referring to their own husband.