Ionic compounds, also known as salt compounds, are formed by the attraction of positively charged ions and negatively charged ions, to create a molecule that is electrically neutral. Synonyms for the term ionic compound include salts, ionic salt, and electrovalent compound. These compounds are formed by the transfer of electrons, which results in the formation of a crystal lattice structure. Other synonyms include inorganic salts, ionic crystals, and cationic-anionic compounds. Ionic compounds are commonly found in nature, such as in sea salt or limestone. They also have a wide variety of applications, including in batteries, chemical reactions, and in the pharmaceutical industry.