Today's DSLR cameras use a two curtain focal plane shutter.
At left is an image of a two curtain focal plane shutter part way through the sequence of making an exposure. The image sensor is immediately behind the curtains.
This shutter was set to 1/500th of a second. Both curtains move from the top to the bottom. The front curtain is released first and in this image is near the bottom of it's range of travel below the black horizontal gap low in the image. The rear curtain follows close behind due to the the 1/500th of a second shutter speed.
The gap between the two curtains travels down and is spaced to expose each part of the image sensor for the required 1/500th of a second.
Once the exposure has been made both curtains get reset to the top of the frame so they are ready for the next exposure.
If the shutter had been set to 1/60th of a second the front curtain would travel all the way down before the