Digital cameras with face detection technology can detect a human face in the frame and automatically focus on it. The focus is based on the detection contrast whereby the lens tries to focus by moving forwards and backwards, while the sensor monitors the photographed image.
EF lenses (Electro Focus) automatically focus electronically using a motor that is built into the lens body. They focus very fast and quietly. EF-S lenses (Electro Focus Short Back Focus) is designed for digital SLR cameras with smaller APS-C sensors, and sit closer to the sensor than EF lenses.
ISO specification indicates the camera sensor's sensitivity to light. Higher sensitivity is primarily used in low light conditions to avoid unwanted noise and blur.
Scene modes adjust the camera settings according to the specific requirements of certain conditions. For example, Night Scene Portrait mode sets the flash device, adjusts the exposure, and so on.
The Live View function enables you to view the image area on the LCD display instead of the viewfinder. The displays are located on the back of the digital SLR body. Some cameras feature a vari-angle LCD display for comfortable shooting.