What's the difference.
Same difference between a tree, a rock, and a rocket ship. Totally different things:
Declarations are used in support of motions. Answers are filed in response to a Complaint. Response to motion (usually called an "opposition to motion") is ... well, and opposition to a motion filed by another party.
The above is general legal and business analysis. It is not "legal advice" but analysis, and different lawyers may analyse this matter differently, especially if there are additional facts not reflected in the question. I am not your attorney until retained by a written retainer agreement signed by both of us. I am only licensed in California. See also avvo.com terms and conditions item 9, incorporated as if it was reprinted here.
An answer is the respondent's pleading which, well, answers the allegations of the initial petition or complaint. The respondent either admits the allegation, denies the allegation, or state there is presently insufficient information to admit or deny, and for that reason denies the allegation.
A response is where one replies to the assertions made in the motion being addressed.
A declaration is generally a statement made by a person under penalty of perjury.
An Answer is a response to a complaint or cross-complaint.
A response to a motion is just that a response to a motion filed by another party. It would typically include a memorandum of points and authorities and maybe a declaration. The type of motion would dictate what needs to be included in the response.
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