What is the difference between an LP, EP, 45 & 78 record?

The terms LP record (LP or 33⅓ rpm record), EP, 16⅔ rpm record, 45 rpm record, and 78 rpm record each refer to specific types of records. LP and EP (Long Play and Extended Play respectively), refer to their speeds in revolutions per minute (rpm). LPs, 45s, and 16s are usually made of polyvinyl chloride (PVC), or simply vinyl.   The average LP had about 1,600 feet of groove on each side, or about a third of a mile. The needle travels approximately 1 mph on average

How does a CD work differently than a vinyl record?

A Compact Disc (CD) is an optical disc used to store digital datea.  Available on the market since late 1982, the first CD pressed was a recording of Herbert von Karajan conducting the Alpine Symphony.

What is the maximum length of USB cable that can be used with a USB turntable to get the optimum sound reproduction?

The maximum length of a standard USB 2.0 cable is 5.0 meters (16.4 ft). The primary reason for this limit is the maximum allowed round-trip delay of about 1500 ns. If a USB device does not answer to host commands within the allowed time, the host considers the command to be lost.  The USB 2.0 specification states that the cable delay must be less than 5.2 ns per meter, which means that maximum length USB cable is 5 meters long.

What is difference between the Turntable Tone Arm, the Cartridge, and the Needle?

The tone arm holds the cartridge over the groove, the stylus (Needle) tracking the groove with the desired force to give good tracking and minimizing wear of the stylus and record groove. At its simplest, a tone arm is a pivoted lever, free to move vertically and horizontally with a counterbalance to maintain tracking pressure.

I see a 78 rpm speed on a turntable, but I never see the 78 speed vinyl records.  What is it for?

The 78 rpm record was generally the standard format pre -World War II.  After World War II, two new competing formats came on to the market and gradually replaced the standard "78".  The 33 1/3 rpm LP (for "long play") format was developed by Columbia Records and marketed in 1948. RCA Victor developed the 45 rpm format and marketed it in 1949. 

How did the Juke Box get its name?

The first jukebox was produced in 1927 by Rowe International. The term "juke box" came into use in the in the 1930s, derived either from African-American slang "jook" meaning "dance". The shellac 78 rpm record dominated jukeboxes until the Seeburg Corporation introduced an all 45 rpm vinyl record jukebox in 1950

Why is there a specific needle for 78 rpm records?

The groove size on old 78 rpm records were wider than were produced on 33 1/3 rpm and 45 rpm records (Microgooves).  A 78 rpm stylus (needle) has a 3 mil (0.08mm) diameter, while a 33 1/3 rpm and 45 rpm record needle has a 1 mil (0.03mm) diameter.   While a 78 rpm record can be played using a 33 1/3  stylus, the best fidelity is obtained by using a 3 mil needle.