Definition: x

(1) For Twitter history, see Twitter.

(2) For current X/Twitter offerings, see X/Twitter.

(3) For Twitter rebranding, see X.com.

(4) For the windowing system, see X Window.

(5) An Alphabet subsidiary. See Alphabet and Google X.

(6) The symbol to close a window. See X button.

(7) For Qualcomm's system-on-chip, see Snapdragon X.

(8) (heX) The symbol for a hexadecimal number. For example, both "0x0A" and "\x0A" specify the hex number 0A. See hex.

(9) (times the original) For example, 10x means 10 times something. Optical drives use the x for their speed ratings (see CD-ROM drives and DVD drives).

(10) (x-) The prefix used to describe a MIME type; for example, x-pdf and x-gzip refer to PDF and Gnu ZIP file formats, respectively. See MIME type.

(11) (x = cross) See cross platform.

(12) For the earlier Mac operating system, see Mac OS X.

(13) (eXperience) See UX designer and user experience.