【Memory】 , 【remembrance】 ,  【recollection】 ,  【reminiscence】 ,  【mind】 ,  【souvenir】  are comparable though not wholly synonymous terms since all involve the ideas of remembering and of being remembered.

【Memory】 applies chiefly to the power or function of remembering what has been experienced or learned; in this sense it suggests the power to reproduce images of what is no longer before one, to retain something (as words, ideas, or skills) that has been learned, and to recognize and identify something previously known.

【Memory】  often occurs in the sense of something remembered either as an aggregate or as a single item. More than the other words  【memory】 as used in this sense suggests a keeping in 【mind】 rather than a bringing back and often, therefore, a treasuring as something intimate or personal.

【Remembrance】 applies primarily to the act or the process, as distinguished from the faculty, power, or function, of remembering.

【Remembrance】 also denotes the state or fact of being kept in the 【memory】 .

【Recollection】  often takes the place of  【remembrance】 but it may carry a strong suggestion of more voluntary and sometimes even more effortful recalling to 【mind】 often of something forgotten or for long unconsidered.

But  【recollection】 is quite as often used of something remembered, especially as the result of conscious effort.

【Reminiscence】  carries a stronger implication of recovery through retrospection than any of the other terms. Like  【remembrance】  and  【recollection】 it denotes either the act or the process of remembering but it further suggests the 【recollection】 of what has been long unremembered, especially because it belongs to one's remote past.

The term is often used in place of  【recollection】 in the concrete sense where what is remembered serves as a contribution to biography, an autobiography, or a history or is recalled from the past in conversation or in writing by an aging or aged person or is a phrase, a passage, a thought, or a custom that is so like one found in an earlier writer or people as to be regarded as an unconscious imitation or repetition or a survival.

【Mind】  (see also  【MIND】 2 ) is found in the sense here considered chiefly in certain idiomatic phrases where it means either the entity (as distinct from the function) which stores up what is remembered or the power to remember.

【Souvenir】 , which more commonly denotes a material memento, may sometimes replace  【memory】 .