What it means
より marks the item used as the standard of comparison and is usually translated as “than.” The compared item commonly appears before は, and the standard appears before より. The adjective or other predicate after the comparison states how the two items differ. より itself does not change for politeness; politeness is shown by the sentence ending.
Usage note
Do not confuse より with ほうが, which marks the item that has more of a quality in a comparison. For example, AはBより大きい means “A is bigger than B,” while Aのほうが大きい also means “A is bigger,” with A explicitly marked as the superior side.
How to use it
このかばんはあのかばんより軽いです。
This bag is lighter than that bag.
このかばんはあのかばんより軽い。
This bag is lighter than that bag.
Example sentences
電車はバスより速いです。
Trains are faster than buses.
図書館は学校より静かです。
The library is quieter than the school.
この道はあの道より安全です。
This road is safer than that road.
春は冬より暖かいです。
Spring is warmer than winter.
りんごはみかんより安いです。