Several parts combine into one character.

Compound ideograph: 宀 (roof, the "house lid" radical) + 豕 (pig). The encoded definition is delightfully agricultural: "if there's a pig under your roof, that's a home". In ancient Chinese farming, livestock were kept inside the dwelling — your home was wherever your pig was. Identical across 繁體 / 新字体 / 简体. This is one of the most pedagogically charming compound characters in the script.

家 spreads across three major meaning domains: — House / home (physical): 家屋 (house), 我が家 (my home). — Family: 家族 (family), 家人 (family members), 国家 (nation — "the great family / country"). — Specialist suffix: ~家 = "expert in / practitioner of". 作家 (writer), 画家 (painter), 専門家 (specialist), 政治家 (politician), 音楽家 (musician).

The 〜家 suffix is one of the most productive in CJK languages and lets you derive professional names from any field with a noun and 家.

Mandarin: jiā, level 1st tone. 家 (jiā, home / family), 国家 (guójiā, nation / state — "country-family"), 家人 (jiārén, family member), 大家 (dàjiā, "everyone / all of you" — literally "big family"), 回家 (huíjiā, go home — extremely high-frequency phrase). The 大家 sense — meaning "everyone gathered together" — captures the Chinese ideal that society is one big family.

Japanese: TWO on-readings split by usage. カ (ka) is dominant — 家族 (kazoku, family), 家庭 (katei, household / domestic life), 国家 (kokka, nation), 作家 (sakka, writer), 漫画家 (mangaka, manga artist). ケ (ke) is rarer — 本家 (honke, main family branch), 大家 (ōya, landlord). Kun-readings: いえ (ie, house — formal) and うち (uchi, home / inside — casual / inclusive). Note うち also means "we / our group" by extension — 内 in some contexts but the 家 reading carries the family-warm sense.

Memory aid: a roof above a pig — agricultural family life encoded in one character.