= JavaScript
A scripting language developed by Netscape Communications and
Sun Microsystems that is loosely related to Java. JavaScript,
however, is not a true object-oriented language, and it is limited
in performance compared with Java because it is not compiled. Basic
online applications and functions can be added to Web pages with
JavaScript, but the number and complexity of available application
programming interface functions are fewer than those available with
Java. JavaScript code, which is included in a Web page along with
the HTML code, is generally considered easier to write than Java,
especially for novice programmers. A JavaScript-compliant Web
browser, such as Netscape Navigator or Internet Explorer, is
necessary to run JavaScript code. = = job queue = = A list of
programs or tasks waiting for execution by a computer. Jobs in the
queue are often ordered according to some basis of priority. = =
Jukebox
Software that is designed to play a list of sound files in a
user-specified order reminiscent of jukeboxes used to play vinyl
records. = = Jumper (computing) = In electronics and particularly
computing, a jumper is two or more connecting points that can be
conveniently shorted together to setup or adjust a printed circuit
board, such as a computer's motherboard.
Jumpers are arranged in groups called jumper blocks, each group
having at least one pair of contact points and often more. In
general, each contact in a jumper block terminates in a small metal
pin. An appropriately sized conductive sleeve called a shunt is
slipped over the pins to complete the circuit. (In everyday usage,
shunts are very commonly but incorrectly called "jumpers".) =
Jitter = Abrupt and unwanted variations of one or more signal
characteristics, such as the interval between successive pulses,
the amplitude of successive cycles, or the frequency or phase of
successive cycles. (188) Note 1: Jitter must be specified in
qualitative terms (e.g., amplitude, phase, pulse width or pulse
position) and in quantitative terms (e.g., average, RMS, or
peak-to-peak). Note 2: The low-frequency cutoff for jitter is
usually specified at 1 Hz. Contrast with drift, wander. = Jerkiness
= In a video display, the perception, by human vision faculties, of
originally continuous motion as a sequence of distinct "snapshots."
Note 1: The perception of continuous motion by human vision
faculties is a manifestation of complex functions, i.e.,
characteristics, of the eyes and brain. When presented with a
sequence of fixed, i.e., still, images of sufficient continuity and
at a sufficiently frequent update rate, the brain interpolates
intermediate images, and the observer subjectively appears to see
continuous motion that in reality does not exist. Note 2: For
example, the update rate of NTSC television displays is 30 frames
(60 fields) per second. = Jam signal = A signal that carries a bit
pattern sent by a data station to inform the other stations that
they must not transmit. Note 1: In carrier-sense multiple access
with collision detection (CSMA/CD) networks, the jam signal
indicates that a collision has occurred. Note 2: In carrier-sense
multiple access with collision avoidance (CSMA/CA) networks, the
jam signal indicates that the sending station intends to transmit.
Note 3: "Jam signal" should not be confused with "electronic
jamming." = Jajah = Jajah is a proprietary peer-to-peer internet
telephony (VoIP) softphone. With Jajah you can speak to other
Jajah-, SIP-, IAX- or Skype-users for free. = Jabber = In local
area networks, transmission by a data station beyond the time
interval allowed by the protocol.
