The electric bass guitar is a bit of a bizarre instrument. It is probably one of the few electrified instruments that doesn't resemble the acoustic instrument it was modeled after. Somewhere in the 20th Century, someone had the idea to put the thick strings of a string bass on the body of an electric guitar (with a long neck). Think of someone wanting to create an electric cello and mounting four strings on the body of a banjo. So people have a difficult time figuring out what an electric bass is -- this is the same reaction that my folks had when they bought me an electric bass for my 16th birthday. "Is it a guitar?" No.
"Well, what is it?"
To my chagrin I would also learn that the girls in my high school had this reaction too. Sometimes, laymen (and laywomen) don't know what to do with the bass player.
But what is important to remember about the electric bass is that it is one of the most important instruments that you will ever forget you heard. It is an extremely important component to pop music -- it lays down foundational rhythms that operate at a deceptively subtle level. Everyone's heard the Beatles and everyone can recognize Paul McCartney's voice. Listen carefully to the bass of a Beatles tune like "Taxman" sometime and you'll really appreciate just how important McCartney was to that band. The bass is a key melodic voice that propels the rhythm of a song.
Like its cousin the guitar, the strings of an electric bass are tuned to EADG. As I also have written in the guitar section of this site, chords are possible with a bass guitar, but they generally aren't played. Those low strings simply don't seem to sound the same.
But the low register of the bass allows it to play single notes that have a certain... gravitas. There is an unmistakable thump that emanates from an electric bass that permeates a wide musical spectrum-- you can hear it in everything from Outkast, to Cream, to the Ramones, to Yes to John Lee Hooker, to Weather Report.
Almost everybody starts out playing the bass by simply mimicking what the guitar plays -- if the guitar plays an A chord, the bass plays an A note, if the guitar plays a B minor chord, the bass still plays a B note. In some styles, like punk, the bassist may continue to play in this sort of method long after his or her technique improves.
But playing along with the guitar is uninspiring. There are much more interesting aspects of playing the bass...