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The Icon is a symbolic image that helps users quickly and simply identify the contente.g. A print icon next to a text box means you can print the contents of that text box
This component allows showing the Icon from the SLDS
So you can refer to the documentation from SLDS https://www.lightningdesignsystem.com/icons/
e.g. Action icons, Custom Icons, Standard Icons, Doctype Icons, Utility Icons
Attributes
Name
You can enter the name of the Icon in the Name attribute
Eg:e.g.
Name: account_info
Name: custom7 
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Size
Adjust Icon sizes using the size attribute with one of these values
There are five types of size
In the Size drop-down, select the size
XX-Small: You can set xx-small size on the icon
X -Small: You can set an x-small size on the icon
Small: You can set a small size on the icon
Medium: You can set medium size on the icon
Large: You can set the large size of the icon
e.g: .
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Category
You can change icons by using their category
The icon comes in five categories
In the Category drop-down, select the category
Action: Action icons are for use with quick actions on touch-screen devices
Custom: Custom Object icons represent the entities and objects
Doctype: Doctype icons represent document file formats:
Standard: Custom Object icons represent the entities and objects
Utility: Utility icons are simple symbols in a single color that identify labels and actions across many form factors
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You can enter a color in the Fill Color attribute
Eg: The icon e.g, The Icon is displayed in red if you enter that color
Fill color: Red
