Several parts combine into one character.

好 is one of the most quietly profound encodings in the script: 女 (woman) + 子 (child) = good. A mother holding her child is what "goodness" looks like. The compound ideograph (会意字) freezes a single observation into a permanent definition. Identical across 繁體 / 新字体 / 简体.

This character is also the absolute first word every Mandarin learner meets: 你好 (nǐ hǎo) — "hello", literally "you-good". 好 anchors Chinese politeness, agreement, and approval more than almost any other character.

Mandarin: hǎo, dipping 3rd tone in most uses. The character carries a tone shift that learners must absorb early — when 好 means "to like / be fond of", it shifts to 4th tone hào: 爱好 (àihào, hobby), 好奇 (hàoqí, curious — "fond of strange things"), 好客 (hàokè, hospitable — "fond of guests"). So 好 is another 破音字: hǎo "good" vs. hào "to be fond of".

Usage map for 好 (hǎo): 好的 (hǎo de, "OK"), 好像 (hǎoxiàng, seems like), 好处 (hǎochù, advantage), 你好吗? (nǐ hǎo ma, "how are you?"), 真好 (zhēn hǎo, really good).

Japanese: on-reading コウ (kō) in 好意 (kōi, goodwill), 好奇心 (kōkishin, curiosity), 好物 (kōbutsu, favorite food), 友好 (yūkō, friendship). Kun-readings split: この.む (kono.mu, to be fond of) — formal verb; す.く (su.ku, to like) — everyday verb, opposite of 嫌う (kirau, to dislike); よ.い / い.い (yo.i / i.i, "good") — by far the most common Japanese adjective. Beginner Japanese textbooks introduce いい on page one.

Note: in Japanese, the kun-reading いい is sometimes written 良い (using 良) rather than 好い, while the verbal "to like" tends to use the suffix +好き (suki). The character family is split across multiple kanji in modern usage.

Memory aid: a woman cradling a child — the original picture of "good".