Spherical geometry other geometric concepts are defined as in plane geometry, but with straight lines replaced by great circles. Thus, in spherical geometry, angles are defined between great circles, resulting in a spherical trigonometry that differs from ordinary trigonometry in many respects; for example, the sum of the interior angles of a triangle exceeds 180 degrees. Spherical geometry is "not" elliptic geometry, but is rather a "subset" of elliptic geometry. For example, it shares with that geometry the property that a line has no parallels through a given point. Contrast this with Euclidean geometry, in which a line has one parallel through
BASIC A+ a supplement to the latter's reference manual as its documentation. In addition to being faster than its ROM-bound counterpart, BASIC A+ provided a number of extra commands for DOS operations, player/missile graphics, and debugging. BASIC A+ BASIC A+ was developed by Optimized Systems Software of Cupertino, California, United States, to provide the Atari 8-bit family with an extended BASIC compatible with, but faster than, the simpler ROM-based Atari BASIC. While Atari BASIC came on an 8 KB ROM cartridge, BASIC A+ was delivered on floppy disk and took 15 KB of the computer's RAM, leaving 23 KB available for user