tissue 纸巾
one is the stuff that makes the human body （人体）组织
other one we clean our face and other parts of the body 纸巾

facial tissue 面巾纸
Kleenex ：舒洁（Kleenex）是全球最知名的面巾纸品牌之一，在口语当中，直接说这个单词，可以表示纸巾
Hey, can you pass me the Kleenex I think I have a cold.
可以给我点递点纸巾吗？我觉得我感冒了。

toilet paper 卫生纸
Hey, they have a sale on toilet paper today.
他们今天卫生纸在大减价呢。

napkin 餐巾纸
a square piece of cloth or paper used at a meal to wipe the fingers or lips and to protect garments, or to serve food on
西方餐桌上供应或使用的餐巾纸，也可以指那种西方人进餐时候围在脖子上好像布一样的东西，napkin 还有尿布的意思
He dabbed at his lips with the napkin.
他用餐巾拭了拭嘴唇。

卷纸：toilet rolls
厨房卷纸：kitchen rolls
单层：single ply
双层：double ply