Tide is the rise and fall of the water’s surface. The tidal range is the amount of difference in low tide and high tide. Tidal range and its resulting effect on the depth of the water may be insignificant in some areas but in others you may have tides that rise and fall up to fifty feet.
Tides are predictable and you should always consult the tide tables when operating in shallow waters.
Current is the flow of the water either from or to the sea as the tide rises and falls. You should be aware of the effects of current on your boat. Current may flow as rapidly as five knots. If you lose an engine and are pushed along with current, you could be swept out to sea or pushed aground.