Wallpaper abstract black background and bright colorsWallpaper abstract black background and bright colors
Rainbow stripes with bends are joined in the centerRainbow stripes with bends are joined in the center
Wallpaper in the form of a clock on a background of the same colorWallpaper in the form of a clock on a background of the same color
В математике: всякая непрямая линия. Кривая линия, изображающая рост или падение чего-н. в развитии какого-н. процесса.