Watch the Bending Notes online guitar lesson by Jennifer Batten from Rock Sauce For Lead Guitar
Bending notes allows a higher level of expression than to just play one note and then the next. It gives you more freedom like a vocalist has, to gliss from one note to the next. To practice, play your target note before bending, to get it into your ear. Then bend a lower pitch up to match the target pitch.
Different permutaions would be:
bend up and stop (mute) or bend up and then go to another note
bend up before picking, then release the bend
bend up and down
bend up and down and then continue higher either by doing a larger bend in the same position, or sliding to the next scale tone on the same string and bending that