xDSL.   DSL,   , , ADSL, HDSL,
SDSL  VDSL.

Xinerama.  XFree86 Release 6 Version 4.0 (X4.0). Xinerama  -
           
  . .  Xinerama-HOWTO.

XML.    (Extensible Markup Language).  
     Web.   W3C, 
XML    SGML. . www.w3.org/XML  www.w3.org/XML/
1999/XMLin-lO-points.

XSM.    (X Session Manager).     ,
  .      
  (  )    (-
     ).        -
     ,        .

Z Shell, zsh. ,     Bourne Again Shell, Korn
Shell  TZ Shell,     .

Zulu time ( ). . UTC.

 .1. , 	  
 	-			-
1	1	1	17	21	11
2	2	2	18	22	12
3	3	3	19	23	13
4	4	4	20	24	14
5	5	5	21	25	15
6	6	6	31	37	1F
7	7	7	32	40	20
8	10 	8	33	41	21
9	11	9	64	100	40
10	12		96	140	60
11	13		100	144	64
12	14		128	200	80
13	15	D	254	376	FE
14	16	E	255	377	FF
15	17	F	256	400	100
16	20	10	257	401	101

 .  1001