These work pretty much like the normal GUI functions - and also have matching implementations in EditorGUILayout.
| actionKey | Is the platform-dependent "action" modifier key held down? (Read Only) | 
| indentLevel | The indent level of the field labels. | 
| showMixedValue | Makes the following controls give the appearance of editing multiple different values. | 
| BeginChangeCheck | Check if any control was changed inside a block of code. | 
| BeginDisabledGroup | Create a group of controls that can be disabled. | 
| BeginProperty | Create a Property wrapper, useful for making regular GUI controls work with SerializedProperty. | 
| BoundsField | Make Center & Extents field for entering a Bounds. | 
| ColorField | Make a field for selecting a Color. | 
| CurveField | Make a field for editing an AnimationCurve. | 
| DelayedDoubleField | Make a delayed text field for entering doubles. | 
| DelayedFloatField | Make a delayed text field for entering floats. | 
| DelayedIntField | Make a delayed text field for entering integers. | 
| DelayedTextField | Make a delayed text field. | 
| DoubleField | Make a text field for entering doubles. | 
| DrawPreviewTexture | Draws the texture within a rectangle. | 
| DrawRect | Draws a filled rectangle of color at the specified position and size within the current editor window. | 
| DrawTextureAlpha | Draws the alpha channel of a texture within a rectangle. | 
| DropdownButton | Make a button that reacts to mouse down, for displaying your own dropdown content. | 
| DropShadowLabel | Draws a label with a drop shadow. | 
| EndChangeCheck | Ends a change check started with BeginChangeCheck (). | 
| EndDisabledGroup | Ends a disabled group started with BeginDisabledGroup. | 
| EndProperty | Ends a Property wrapper started with BeginProperty. | 
| EnumMaskField | Make a field for enum based masks. | 
| EnumMaskPopup | Make an enum popup selection field for a bitmask. | 
| EnumPopup | Make an enum popup selection field. | 
| FloatField | Make a text field for entering floats. | 
| FocusTextInControl | Move keyboard focus to a named text field and begin editing of the content. | 
| Foldout | Make a label with a foldout arrow to the left of it. | 
| GetPropertyHeight | Get the height needed for a PropertyField control. | 
| HandlePrefixLabel | Make a label for some control. | 
| HelpBox | Make a help box with a message to the user. | 
| InspectorTitlebar | Make an inspector-window-like titlebar. | 
| IntField | Make a text field for entering integers. | 
| IntPopup | Make an integer popup selection field. | 
| IntSlider | Make a slider the user can drag to change an integer value between a min and a max. | 
| LabelField | Make a label field. (Useful for showing read-only info.) | 
| LayerField | Make a layer selection field. | 
| LongField | Make a text field for entering long integers. | 
| MaskField | Make a field for masks. | 
| MinMaxSlider | Make a special slider the user can use to specify a range between a min and a max. | 
| MultiFloatField | Make a multi-control with text fields for entering multiple floats in the same line. | 
| MultiPropertyField | Make a multi-control with several property fields in the same line. | 
| ObjectField | Make an object field. You can assign objects either by drag and drop objects or by selecting an object using the Object Picker. | 
| PasswordField | Make a text field where the user can enter a password. | 
| Popup | Make a generic popup selection field. | 
| PrefixLabel | Make a label in front of some control. | 
| ProgressBar | Make a progress bar. | 
| PropertyField | Make a field for SerializedProperty. | 
| RectField | Make an X, Y, W & H field for entering a Rect. | 
| SelectableLabel | Make a selectable label field. (Useful for showing read-only info that can be copy-pasted.) | 
| Slider | Make a slider the user can drag to change a value between a min and a max. | 
| TagField | Make a tag selection field. | 
| TextArea | Make a text area. | 
| TextField | Make a text field. | 
| Toggle | Make a toggle. | 
| ToggleLeft | Make a toggle field where the toggle is to the left and the label immediately to the right of it. | 
| Vector2Field | Make an X & Y field for entering a Vector2. | 
| Vector3Field | Make an X, Y & Z field for entering a Vector3. | 
| Vector4Field | Make an X, Y, Z & W field for entering a Vector4. |