Elements of Photography:
Line
Guides the viewers eyes to the main subject. Can be vertical, horizontal, curved or jagged.
Your eyes follow the line whether it is visible or invisible.
Based on its character and direction, lines communicate emotions making it one of the strongest elements of design.
Horizontal lines suggest feeling of restfulness or calmness
Vertical lines suggest feeling of power
Diagonal lines suggest feeling of movement and direction
Soft curved lines represents relaxing or soothing feel whereas acute or jagged lines suggest frenzy or chaotic feeling and so on