Data annotation is the process of labelling data and meta data in order to train computer-vision-based algorithms. This information might take the shape of text, videos, photographs, social media material, and so on. Labelling, on the other hand, is done with tags, making it easier for AI-based classifiers to compute characteristics. Annotation in machine learning is developed to ensure the target of interest is observable or recognizable. Semantic segmentation, lines and splines, bounding boxes, 3D cuboid annotation, polygons, phrase chunking, text classification, entity linking, and many other approaches are examples of data annotation techniques.