This report examines the characteristics and first-year behaviors of beginning postsecondary students entering public 2-year, public 4-year, and private, not-for-profit 4-year institutions of higher education, based on data derived from the 1995-96 National Postsecondary Student Aid Study. The report begins with an essay that describes the characteristics of beginning students in each sector. Among findings are the following: (1) public 2-year institution entrants are more likely than those entering 4-year institutions to be older, have independent financial aid status, plan to complete a lower level of postsecondary education, and have lower scores on college admission tests; (2) freshmen entering private not-for-profit 4-year institutions are more likely that those at 4-year public institutions to have families with higher incomes, to have higher college admission test scores, to attend full-time, and to have more and differently packaged financial aid; and (3) freshmen at 2-year institutions are more likely to interrupt their enrollment before the end of their first year. The essay is followed by a compendium of tables that provides comprehensive information about enrollment, academic activity, background characteristics, financial aid, employment, educational plans, life goals, institutional involvement, and community involvement. A glossary and technical notes are appended. (DB)