Annotation refers to the process of marking and annotating documents or works, with the purpose of expressing the author's views or evaluating the content. In some commercial or scientific research fields, annotations are also widely used to review documents and papers. Annotation can quickly and accurately reflect the advantages and disadvantages of documents or papers, and then modify and improve them.

In the digital age, annotations are becoming more and more popular. By tagging electronic documents, not only can they be modified and sorted quickly, but also the security of the documents themselves can be guaranteed. Annotation function is also involved in some software, such as drawing software and PDF reader. These softwares allow users to easily annotate and evaluate the contents of images or documents.

For the use of annotations, we need to improve the professionalism and accuracy of annotations to a certain extent. Annotation, as an additional information, needs to pay attention to tone, words and other issues when expressing, and try to avoid ambiguous expression. In addition, when documents involving intellectual property rights and trade secrets are marked, confidentiality rules should also be observed to avoid unnecessary information disclosure. In practical application, labeling techniques and strategies should be used reasonably according to the requirements of different fields and scenes.