When you add a shot to the Timeline, it automatically creates a splice. A splice is where one element ends and the following element begins, creating a hard transition. It is also possible to add a splice to an element in the Timeline to divide the element into two sections. You can remove a splice from an element, creating a continuous element.
To add a splice:
Click and drag the focus point to the layer you want to splice.
Move the positioner to the exact location of the element you want to splice.
Click Cut.
A splice is added.
To remove a splice:
Place the positioner on the right-most (also known as the B) side of the previously cut shot.
Click Join.