A bass Guitar also called an electric bass
is a stringed instrument played primarily with the fingers or thumb, by
plucking, slapping, popping, (rarely) strumming, tapping, thumping, or picking
with a plectrum, often known as a pick.
The bass guitar is similar in appearance and construction to an electric guitar, but with a longer neck and scale length, and four to six strings or courses. Like the electric guitar, the bass guitar is plugged into an amplifier and speaker for live performance. The simplest difference between guitar and bass guitar is the pitch range of the instruments. Think of the song Another One Bites the Dust by Queen. The first few notes you hear are the sound of the bass guitar. In fact, that is the sound of the lowest note on the most common type of bass guitar.
Bass Guitar, with its higher range, also plays a supportive role and solos are more common on guitar. Traditionally guitar is a bit more out front and in the spotlight. But, the bass is very critical in a band. You will see many bands without guitarists and without drummers, but not many without a bass player. That should tell you the importance of the bass guitar in a band. Furthermore, the bass still has all the same possibilities as the guitar. You can solo and play many things like a guitarist does.