Key Difference: Appendix is a document that is attached to the end of research project or a dissertation in order to strengthen the data in the document. An annex contains data that could back the matter in the project or thesis.

Appendix and annex are concepts that are used during research projects, dissertations, books and legal documents. Due to their selective usage, many people are oblivious to these terms until they have to write proper research papers in colleges. Though these are similar in the sense that they belong at the end of the document, they differ from each other in many ways including usage and purpose.

Appendix is a document that is attached to the end of research project or a dissertation in order to strengthen the data in the document. The purpose of an appendix is to further explain and clarify the matter that is in the project or other literary works. An appendix could also be a part of the book, which explains details or the background story that may not be clear to a reader. The appendix goes together with the document and cannot be submitted without the whole document. An appendix could also include graphs, pictures, glossaries or any other text that may make the original document easier to understand. In some literature books, towards the end of the pages includes a glossary or a description or a map even, these are all part of the appendix.

Dictionary.com defines ‘appendix’ as:

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• A body of separate additional material at the end of a book, magazine, etc., esp one that is documentary or explanatory
• Any part that is dependent or supplementary in nature or function; appendage

An annex is complete separate document that can also be considered as a standalone document. An annex contains data that could back the matter in the project or thesis. These are commonly used in order to back up research in the thesis or research projects. An example of an annex would be additional research that may be done by other resources, which could contribute to your research or could be completely different from your research. This would not hinder the research in anyway, but does add greater value to the overall research. The annex does not necessarily have to be written by the author is more commonly written by other authors. An appendix is a kind of an annex; however an annex is not an appendix.

Dictionary.com defines ‘annex’ as:

• To append or attach, especially to a larger or more significant thing.
• To incorporate (territory) into an existing political unit such as a country, state, county, or city.
• To add or attach, as an attribute, condition, or consequence.
• A building added on to a larger one or an auxiliary building situated near a main one.
• An addition, such as an appendix, that is made to a record or other document.

In legal terms, an appendix or an annex is also known as addendum, which is an additional part of a legal document that may have sub-points that are not explained directly in the main agreement. It is used in reference to contracts and agreements, with annex and appendixes used to make the whole agreement clear or add points that are eliminated in the original contract.

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