A boat can sail into the wind by sailing backwards and forwards (tacking) at an angle to the wind and so making her way up.
A sailing boat can not sail directly upwind, sail at about 45 degrees to the wind and tack (turn the boat through the wind) to the other side of the wind and continue in this zig-zag manner up wind.
it depends on the type of sailboat, the wind strength
A sail is a piece of fabric attached to a boat, causing the wind to drive the boat along.
To sail against the wind, a boat has to 'tack'. This means that instead of sailing straight into the wind (which would get you nowhere) you sail in a zig-zag in the direction you intend to go. On each tack, the wind is on a different side of the sail.
a boat a sail and the wind
the force is there and it is easier to row
A little wind can move a boat depending on the size and weight of the boat.
With a square rigged sail, the wind simply pushes the boat along. With a fore and aft rigged sail, the wind is caught at an angle and slices on past the sail, pushing the sail hard down wind and a bit forward. A deep keel on the bottom of the sail boat tries to stop the downwind drift and, as a result of a bit of a push forward on the sail, the sail boat manages to scoot across the wind a bit. Square rigged ship: http://sailing-ships.oktett.net/golden-state.jpg The wind just blows the boat down wind. Fore and aft rigged sailboat (a sloop) http://2.bp.blogspot.com/_98ZiJEAKrlI/Rql8iSS1u5I/AAAAAAAAFc4/hwyku_OY29E/s400/9%2Bsm%2Bsb%2Bpassing.jpg Note that the sail boat is tipped over a bit (heeling). This is due to the wind trying to push the sail boat down wind and the bottom of the sail boat (the keel) trying to stop the drift down wind. The wind is slicing off the sails and pushes the sail boat a head a bit.