Final answer:
A covalent bond is the attachment between atoms that involves sharing one or more pairs of electrons, distinct from an ionic bond, which involves electron transfer.
Step-by-step explanation:
The attachment between atoms that results from the atoms sharing one or more pairs of electrons is known as a covalent bond. Unlike an ionic bond, which involves the transfer of electrons from one atom to another resulting in the formation of ions, a covalent bond joins atoms by allowing them to share valence electrons. This kind of bonding often occurs between nonmetal atoms with similar electronegativity values, which is the ability of an atom to attract shared electrons in a chemical bond. Molecules like water (H2O) are classic examples of compounds held together by covalent bonds. The shared electrons allow each atom to achieve a full outer shell of electrons, leading to a more stable arrangement.