1. Guitar: Acoustic or electric guitars often play a central role in many genres, from rock to pop to folk, providing rhythmic accompaniment or intricate melodies.
2. Drums: The drum set, consisting of bass drum, snare drum, toms, cymbals, and hi-hats, is essential in countless styles, establishing tempo, rhythm, and groove.
3. Piano/Keyboard: Pianos or electronic keyboards serve as primary instruments in various genres, from classical pieces to pop ballads, jazz, and electronic music.
4. Vocals: The human voice is arguably the most important "instrument" in a song. Singers use their voices to convey lyrics and emotions, often taking the lead role.
5. Bass Guitar: Bass guitars provide low-end support, rhythmic foundation, and harmonic depth in many genres, including rock, funk, blues, and more.
6. Violin/Strings: Violins, cellos, violas, and double basses are common instruments in classical music and can be featured in various other styles, adding emotional depth and melodic layers.
7. Saxophone: Saxophones are notable in jazz, where they play significant melodic and improvisational roles, but they can also be found in other genres like pop, rock, and blues.
8. Trumpet/Brass Instruments: Trumpets, trombones, and other brass instruments are often featured in jazz, big band music, ska, and brass-infused pop songs.
9. Synthesizers: Electronic synthesizers and samplers allow for a wide range of sounds and textures, making them important elements in electronic dance music (EDM), hip-hop, and pop music.
10. Human Beatbox: Some artists use their mouths and vocal cords to imitate percussive sounds, producing rhythmic beats and patterns without the need for traditional instruments.
It's important to note that the main instrument in a song can vary widely based on genre and the artist's creative choices. Additionally, other instruments like flutes, clarinets, accordions, and more may be featured prominently in different musical styles and compositions.