Hydrogen is a special element because it does not belong to any family. On the periodic table, hydrogen is listed at the top of group one, which contains all alkali metals, but it is not associated with the rest of those elements.
Almost all elements on the periodic table belong to one of the 18 elemental groups. These groups contain atoms that share common properties. The alkali metals, for example, all have one valence electron, like hydrogen. However, other than this structural similarity, hydrogen does not behave like any of the alkali metals. Most notably, hydrogen almost always exists as a gas as a pure substance, while the alkali metals are solids.