Hydrogen's single electron configuration makes it unique. It can lose the electron to form H+, or gain an electron to become H-. It doesn't belong with the alkali metals, and it doesn't belong with the halogens. We don't know quite what to do with hydrogen, and on some periodic tables it floats in the space above the rest of the table- the element without a family.
But helium should not be considered an orphan. It is clearly a noble gas, and belongs above Ne on the table. Although it's different from the others because of its smaller size, the same can be said of the first element in every family.
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Last Revised 02/23/18.URL: http://antoine.frostburg.edu/chem/senese/101/periodic/faq/print-first-period.shtml