Scrambling is a style of ascend lying somewhere between climbing and walking, oftenly distinguished from walking by defining a scramble is where hands must be used in the ascend. There is less to distinguish it from climbing, where many easy climbs are sometimes difficult scrambles. Sometimes ropes are needed for sections of hard scrambles.
In the UK, scrambles are graded from 1, 2, 3, M, D (M and D are climbing grades for moderate and difficult) according to their technical difficulty and exposure.
The North ridge of Tryfan in Snowdonia and Striding Edge on Helvellyn in the Lake District are classic grade 1 scrambles.