Budding is found in both unicellular as well as multicellular organisms. In unicellular organisms, because of the arrangement of nucleus and cytoplasm within single-celled organisms, some parts of the body bulge out as a bud at any point and grow into a complete organism. This organism acts freely after disconnecting from the mother cell. Occasionally, the buds might form a connected chair before breaking up from the parent cell. An example of this would be yeast.
In multicellular organisms such as Hydra, some area of the body increases and grows into a bud. To grow freely as a daughter animal this bud has to break away from its parent’s body.