In Computing
65535 is a frequently occurring number in the field of computing because it is the highest number which can be represented by an unsigned 16 bit binary number. Some computer programming environments may have pre-defined constant values representing 65535, with names like "MAX_UNSIGNED_SHORT". In older computers with processors operating with a 16-bit address bus (such as the MOS Technology 6502 and the Zilog Z80), 65535 was the highest addressable memory location. Such processors thus supported at most 64 kibibytes (64 KiB) of total memory. Of course, this is assuming byte-addressed memory. In Internet protocols, 65535 is also the number of TCP and UDP ports available at an IP address, since port 0 is reserved.
A Java class or interface can have, at maximum, 65535 number of methods. The code of a constructor in Java is limited to 65535 bytes. In some implementations of Tiny BASIC, inputting a command that divides any number by zero will return 65535.
In an unpatched version of Microsoft Excel 2007, many mathematical computations evaluating to 65535 will display incorrectly. For example =850*77.1 displays as 100000 rather than 65535. Microsoft reports this to be a display-only bug for only 6 floating point numbers near 65535 and 65536. These display issues do not occur in editions of Excel that have been updated to Office 2007 service pack 2.
65535 is also the limit for many player variables in video games, such as attack damage in the game "StarCraft", experience points in Dragon Warrior, character stats for Mu Online, maximum enchant of items in Lineage 2, money carried in Phantasy Star and Dark Cloud, elemental attribute points in "Castlevania: Order of Ecclesia", score in Star Wars: TIE Fighter, several limits in Harvest Moon DS, the maximum experience per level in Devil Survivor, the maximum amount of saved fights in The World Ends with You, and the trainer's maximum possible ID number in the Pokémon series.
Read more about this topic: 0x FFFF