A banjo ukulele
The banjo ukulele is a four-stringed musical instrument that is one part ukulele and one part banjo. It was introduced in the early 1900s when ukuleles were becoming a popular instrument in movies and vaudeville. A ukulele is generally a soft-sounding instrument, while a banjo ukulele is quite loud---and this is perhaps why they became so popular, as they could be heard better over a feisty audience back when sound had little to no amplification. Banjo ukuleles are played and tuned like a ukulele, but share the tone and look of a banjo (albeit on a much smaller scale). It goes by many different names: banjo ukulele, banjulele and banjo uke.
Find a comfortable place to sit facing forward---a chair without armrests is perfect. Place the ukulele on its back on your lap, with the strings facing upward toward you.
Tune your banjo ukulele beginning with the top string. Hold the instrument in your lap and turn the tuning pegs slowly counterclockwise while gently plucking the string. A ukulele is commonly tuned to GCEA, with G being the top string.
Use a tuning fork or a piano for reference when tuning. Turn the pegs until each string matches the tone of the note in question. This tuning is typically called "my dog has fleas." Tune the banjo ukulele properly and sing "my dog has fleas," with G being the first note, and you'll understand why. Finally, banjo ukulele necks usually have 16 frets.
Sit with your right leg cross over your left leg. Support the body of the banjo ukulele in your lap, while supporting the neck in your left hand.
Hold the banjo ukulele tight against your chest, close to your diaphragm, while supporting the body of the instrument with your right forearm (alternate method). Some banjo ukuleles can be heavy, depending on the materials used in the construction.
Use your left hand to support the neck, with the neck positioned in the crook between your thumb and forefinger. The tip of your thumb should be gently pressed against the back of the neck for additional support (use your right hand to support the neck if you are left-handed).
Strike the banjo ukulele strings bare-handed or with a pick. If you are using a pick, hold it between the thumb and forefinger of your right hand. A flexible felt pick is recommended, unless you want your banjo ukulele extra loud. In that case, any pick will work.
Play the banjo ukulele as you would a typical ukulele, using the same chord positioning and scales, by moving your left hand up and down the fretboard. If you are not familiar with chords, understand that chords are created up and down the neck by pressing your left-hand fingers down on the fret board, in between the frets. Press until the strings are in contact with the frets (so as to not emit any buzzing).
Move your right hand up and down, either bare-handed or using a pick, until you find a rhythm and while you are holding your left hand in a chord position. If you are having trouble, you may need to take a lesson.
Keep in mind that banjo ukuleles are indeed a joyful instrument, which is why old-time comedy records and television shows feature soundtracks with pronounced banjo ukulele music. It's almost impossible not to smile when you hear one.