Generally to represent something, such as spiritual belief or extreme happiness, that cannot be portrayed in text with such meaning and description of that feeling or belief. For instance, the creation of Adam. You know that painting, right? Well, would it have the same impact on you in printed words as it does in its current form? Ponder that, and then you'll know what an icon is used for.
The Fx icon.
A small square icon.
The Twitter icon is a little blue bird. Presumably they used a bird as they 'tweet'
How a building icon looks will depend on what type of building it is. A building icon is a miniature version of the building used in prototypes and initial planning.
Adding a picture can be in an attachment or in Google Drive. The pin icon can be used to add attachment. The picture icon can be used for Drive.
Probably... you mean the 'Square Face Icon Generator'
The icon typically used to underline text is a U-shaped icon with a line underneath. It is commonly found in word processing or editing tools.
The icon helmets are used to protect words so that they do not get hit on the head. It is very important that words don't get hit on the head because they are very important to our society.
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It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.It is the icon for the Find command.
icon
An open hand holding the folder