The Meaning Behind Shapes. Like colors and fonts, the shapes used

Change the colors in a text box or shape - Microsoft Support

The Principles of Design and Their Importance

Geometric Meanings: The Psychology of Shapes and How to Use Them in Your Designs

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Resources :: Colors, Shapes, Lines

The Psychology of Colors & Shapes - Greyphyte

7 Basic Elements of Design

Decoding Logo Shapes and Their Meanings

Logo Shapes: What They Mean & Why They're Important - Looka

Shapes in English - Basic Shapes and Colours