how many keys does a piano have full size
Piano Most modern pianos have a row of 88 black and white keys, 52 white keys for the notes of the C major scale (C, D, E, F, G, A and B) and 36 shorter black keys, which are raised above the white keys, and set further back on the keyboard. This means that the piano can play 88 different pitches (or "notes"), going from the deepest bass range to the highest treble. The black keys are for the "accidentals" (F♯/G♭, G♯/A♭, A♯/B♭, C♯/D♭, and D♯/E♭), which are needed to play in all twelve keys. More rarely, some pianos have additional keys (which require additional strings). Most notes have three strings, except for the bass that graduates from one to two. The strings are sounded when keys are pressed or struck, and silenced by dampers when the hands are lifted from the keyboard. Although an acoustic piano has strings, it is usually classified as a percussion instrument rather than as a stringed instrument, because the strings are struck rather than plucked (as with a harpsichord or spinet); in the Hornbostel–Sachs system of instrument classification, pianos are considered chordophones. There are two main types of piano: the grand piano and the upright piano. The grand piano is used for Classical solos, chamber music, and art song, and it is often used in jazz and pop concerts. The upright piano, which is more compact, is the most popular type, as it is a better size for use in private homes for domestic music-making and practice.
Macintosh 128K The built-in display was a one-bit black-and-white, 9 in (23 cm) CRT with a fixed resolution of 512×342 pixels, establishing the desktop publishing standard of 72 PPI.[8] Expansion and networking were achieved using two non-standard RS-422 DE-9 serial ports named "printer" and "modem"; they did not support hardware handshaking. An external floppy disk drive could be added using a proprietary connector (19-pin D-sub). The keyboard and mouse used simple proprietary protocols, allowing some third-party upgrades. The original keyboard had no arrow keys, numeric keypad or function keys. This was an intentional decision by Apple, as these keys were common on older platforms and it was thought that the addition of these keys would encourage software developers to simply port their existing applications to the Mac, rather than design new ones around the GUI paradigm.[9] Later, Apple would make a numeric keypad available for the Macintosh 128K. The keyboard sold with the newer Macintosh Plus model would include the numeric keypad and arrow keys, but still no function keys. As with the Apple Lisa before it, the mouse had a single button. Standard headphones could also be connected to a monaural jack. Apple also offered their 300 and 1200 bit/s modems originally released for the Apple II line. Initially, the only printer available was the Apple ImageWriter, a dot matrix printer which was designed to produce 144 dpi WYSIWYG output from the Mac's 72 dpi screen. Eventually, the LaserWriter and other printers were capable of being connected using AppleTalk, Apple's built-in networking system.