When people think of stringed instruments, these days, they probably picture guitars, banjos, violins, or any other instruments that is commonly used in the present music industry. Mostly every stringed instrument that we see today has a long history of its own. However, there are also countless other stringed instruments that have been invented that most people today aren't aware exist. A lot of these instruments are what our present-day instruments have derived from.
One of the oldest recorded stringed instruments is the lyre. In the days of the Old Testament, King David played the lyre while he sang songs to the Lord. The lyre is somewhat similar to a small harp, but it is not necessarily a harp, due to its differences in construction. However, it can be played much similarly to a harp. Harps were also an instrument used during the ancient Old Testament days.
Another instrument that was developed early on, was the ancient European lute. The lute was very common during the Medieval and Baroque eras. What's interesting about the lute, is that it resembles a guitar in a lot of ways. In fact, the classical/acoustic guitar was inspired by the lute's construction. However, there is a definite difference between the sound of a lute and a guitar. Some may say that the lute has a more "harp-like" sound. This is due to the different materials of the strings, as well as the acoustic properties of each instrument. A lute has a rounded dome-shaped back, while a guitar generally has a flat, box-like construction. Both instruments can be strummed, plucked, and finger-picked.
One commonality between the lute and the guitar, is that the body and the finger/fret board are two separate parts. However, there is a family of stringed instruments where the fingerboard and the acoustic body of the instrument are one piece. Such instruments include the Swedish "hummel", the German "Scheitholt", and the Norwegian "langeleik". Not only are these names hard to pronounce, but they're also rarely ever heard. That is due to the fact that these instruments aren't commonly played anymore. They were developed between the seventeenth and nineteenth centuries and they each have a distinct sound. They're primarily played on the lap, or on a table while facing up, as opposed to a guitar, which is played facing away from the musician. They're also small instruments, but are capable of projecting high volumes. They also use frets that are perpendicular to the strings, much like a guitar.
There are hundreds of stringed instruments that have been developed over the centuries. This list is only a small portion of the vast history of stringed instruments. Not to mention, each stringed instrument has many different variants in its design, especially instruments that were built before mass-production methods were used. Before the twentieth century, every stringed instrument was hand-mad by luthiers who had a passion for music. Music has always been an important part of every culture, and every culture has at one point used instruments in its history. Most cultures, if not every culture, has used stringed instrument. The reason why, is because emotions can easily be expressed through the large variety of notes that string systems can produce. Stringed instruments are just as popular today as they have ever been, because of this.