A DICOM file presents data as a sequence of elements containing information about the image (graph etc.), where the last element has the image (graph etc.) itself. Each element comprises several parts, including:
Tag — a unique element identifier comprised of a pair of values represented in the hexadecimal number system and determining the group number and the element number
Data type — a line showing the data type abbreviation (two symbols)
Data field length;
Data — the information comprised in the element, including the image (graph etc.) itself
If the Data field contains information that cannot be represented in the form of a text (e.g. an image or graph), then the respective column will read: Binary content. Hidden.
If the tag is standard, its name will be shown. If the tag is reserved by a certain modality manufacturer or there is an error in its name, then the field will read: Unknown Tag & Data. To learn about the data contained in this tag, you will need to study the documents for the modality used in the study. The 7fe0,0010 (PixelData) tag contains an image, a graph or some other visual data.
Examples of elements:
| Element name | Tag | Type | Length | Data |
| StudyDate | 0008,0020 | DA | 8 | 20130107 |
| StudyInstanceUID | 0020,000d | UI | 56 | 1.3.12.2.1107.5.2.6.24186. 30000013011710501018700000060 |
| Modality | 0008,0060 | CS | 2 | MR |
| Unknown Tag & Data | 0051,1009 | LO | 4 | 1.0 |
| PixelData | 7fe0,0010 | OW | 2 | Binary content. Hidden. |