What is the difference of black and white ultrasound and color ultrasound

1. Black-and-white ultrasound (B-mode ultrasound)   - Shows only grayscale images (black, white, gray).   - Mainly used to observe morphology, structure, size, and position of organs or tissues.   - Like a black-and-white photo of the inside of the body. 2. Color ultrasound (Color Doppler ultrasound)   - Still has the black-and-white structural image, but adds color overlay.   - The “color” shows blood flow direction and speed (red and blue usually represent flow toward or away from the probe).   - Helps diagnose problems related to blood vessels, heart, blood supply, and lesions with blood flow.   - Like a color image with blood flow information, not just a simple color picture. In short: - Black-and-white ultrasound: shows structure. - Color ultrasound: shows structure + blood flow.