本: book; origin; main; counter for long objects. JLPT N5; 5 strokes.
本 means 'book', but also 'origin' and 'main, true'; as a counter it counts long and thin objects.
On readings: ホン in 本 (ほん, book), 日本 (にほん, Japan), 本当 (ほんとう, true), 本日 (ほんじつ, today, formal), 基本 (きほん, base, foundations). As a counter the sound changes according to the number: 一本 (いっぽん), 二本 (にほん), 三本 (さんぼん), 六本 (ろっぽん), 八本 (はっぽん or はちほん), 十本 (じゅっぽん or じっぽん). It is used for pens, bottles, trees and umbrellas, but also for films and phone calls.
Kun reading: もと, 'origin, base', today rarely used alone; it appears in words like 大本 (おおもと, root, source) and in many surnames, such as 山本 (やまもと) and 松本 (まつもと).
Remember: the kanji is obtained from 木 (tree) with a horizontal stroke at the bottom that marks the root; from here the meaning of 'origin'.
この本は面白いです。
kono hon wa omoshiroi desu.
This book is interesting.
Follow the steps in order. Each new stroke is highlighted.
Stroke paths: KanjiVG, CC BY-SA 3.0. Sequential diagrams derived from the original paths.