I really can't tell the difference between these two words, though I looked them up in the dictionary. And it says, "Companion is simply a friend or partner in something you do."; "company is the people you stay with". In that sense, dose it mean I could chose either of them to express same meaning? Is there any difference when these two words are used to carry the meaning of "friend"? Thank you. You will help me much with your explanations. Thanks!
Hi Ahava,

'Companion (s)' means individuals you are closely associated with, and is nowadays used in such phrases as 'travelling companion', 'home companion to a senior citizen', 'companion website', 'companion volume (of a matched set of books)', suggesting a close mutual relationship of some sort.

'Company' has a more general meaning of the people surrounding you, your milieu; it does not suggest such a close interpersonal bond.

A person could enjoy good company without having any close companion among them.

I hope this helps; perhaps another member will be able to expand further.
Thank you Mister Micawber. Thanks for the detailed explaination. Now I could see the difference. Thank you again.Emotion: smile