你，you. 好， good, fine, ok.
您，is a polite way instead of 你， express respect for someone, such as eldership（长辈）, senior citizen（老年人）, parents, leader, business partner, teacher, and so on.
Zǎo shang hǎo nǐ zǎo nǐ hǎo
早上，morning. 早，morning, early.
“你好”is a common greeting and can be used anytime when people meet each other. The answer for “你好” also is “你好”.
3. Good after noon Good evening Good night
xià wǔ hǎo wǎn shang hǎo wān ān
下 午 好 晚 上 好 晚 安
you also can reply 下午好 and 晚上好 with “你好”.