| Caret | A Caret annotation (PDF 1.5) is a visual symbol that indicates the presence of text edits. |
| CheckBoxWidget | An object representing a check box used in a PDF Form. |
| Circle | Square and circle annotations (PDF 1.3) shall display, respectively, a rectangle or an ellipse on the page. |
| ComboBoxWidget | An object representing a Combo Box used in a PDF Form. |
| FileAttachment | A file attachment annotation (PDF 1.3) contains a reference to a file, which typically shall be embedded in the PDF file. |
| FreeText | A free text annotation (PDF 1.3) displays text directly on the page. |
| Highlight | Text markup annotations shall appear as highlights, underlines, strikeouts (all PDF 1.3), or jagged ("squiggly") underlines (PDF 1.4) in the text of a document. |
| Ink | An ink annotation (PDF 1.3) represents a freehand "scribble" composed of one or more disjoint paths. |
| Line | The purpose of a line annotation (PDF 1.3) is to display a single straight line on the page. |
| Link | A link annotation represents either a hypertext link to a destination elsewhere in the document or an action to be performed. |
| ListBoxWidget | An object representing a List Box used in a PDF Form. |
| Markup | The meaning of an annotation's Contents entry varies by annotation type. |
| Movie | The Class Movie. |
| Polygon | The Polygon class. |
| PolyLine | Polyline annotations (PDF 1.5) display (open or closed) shapes of multiple edges on the page. |
| Popup | A pop-up annotation (PDF 1.3) displays text in a pop-up window for entry and editing. |
| PushButtonWidget | An object representing a push button used in a PDF Form. |
| RadioButtonGroup | An object representing a Group of Radio Buttons that can be used to create new Radio Buttons. |
| RadioButtonWidget | An object representing a Radio Button used in a PDF Form. |
| Redaction | A redaction annotation (PDF 1.7) identifies content that is intended to be removed from the document. |
| RubberStamp | A rubber stamp annotation (PDF 1.3) displays text or graphics intended to look as if they were stamped on the page with a rubber stamp. |
| Screen | A screen annotation (PDF 1.5) specifies a region of a page upon which media clips may be played. |
| SignatureWidget | An object representing a Signature used in a PDF Form. |
| Sound | A sound annotation (PDF 1.2) shall analogous to a text annotation except that instead of a text note, it contains sound recorded from the computer's microphone or imported from a file. |
| Square | Square and circle annotations (PDF 1.3) shall display, respectively, a rectangle or an ellipse on the page. |
| Squiggly | TextMarkup annotations shall appear as highlights, underlines, strikeouts (all PDF 1.3), or jagged ("squiggly") underlines (PDF 1.4) in the text of a document. |
| StrikeOut | TextMarkup annotations shall appear as highlights, underlines, strikeouts (all PDF 1.3), or jagged ("squiggly") underlines (PDF 1.4) in the text of a document. |
| Text | A text annotation represents a "sticky note" attached to a point in the PDF document. |
| TextMarkup | Text markup annotations shall appear as highlights, underlines, strikeouts (all PDF 1.3), or jagged ("squiggly") underlines (PDF 1.4) in the text of a document. |
| TextWidget | An object representing a Text Box used in a PDF Form. |
| Underline | Text markup annotations shall appear as highlights, underlines, strikeouts (all PDF 1.3), or jagged ("squiggly") underlines (PDF 1.4) in the text of a document. |
| Watermark | A watermark annotation (PDF 1.6) shall be used to represent graphics that shall be printed at a fixed size and position on a page, regardless of the dimensions of the printed page. |
| Widget | Interactive forms use widget annotations (PDF 1.2) to represent the appearance of fields and to manage user interactions. |