Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
Drop C tuning is an alternative guitar tuning where at least one string has been lowered to a C, but most commonly refers to CGCFAD, which can be described as D tuning with a 6th string dropped to C, or drop D tuning transposed down a whole step. Because of its heavier tone, it is most commonly used in rock and heavy metal music.
Variations
CGDGBE – Dropping the low E string to a C, and the A string to a G, to make a fifth chord. The rest of the strings remain the same.
CADGBE – This is achieved by taking standard tuning (EADGBE), and dropping the low E to a C. All other strings remain in standard tuning.
Artists that have used CGCFAD
Rammstein (On several songs, alternated with DADGBE tuning. The albums Reise, Reise and Rosenrot are almost entirely composed in Drop c)
Aledort, Andy (7 April 2010). "Atreyu: Prior Convictions". Guitar World. Retrieved 23 November 2011. ...drop C tuning, which is like drop D but with all of the strings down a whole step . Drop C sounds a little more brutal. Because of its deeper, heavier sound, it is commonly used in metal.
Mercedes-Benz Enthusiast Channel 1 (12 July 2009), HEAVEN & HELL - Follow The Tears, archived from the original on 13 December 2021, retrieved 5 April 2016{{citation}}: CS1 maint: numeric names: authors list (link)
"Nickelback Equipment". Archived from the original on 20 May 2010. Retrieved 13 May 2014. ...(Drop D One Whole Step Down CGCFAD, Drop C CADGBE and Drop B BADGBE)
Adriaensen, Wouter. "Ruben Block gear". Blues Online. Retrieved 13 May 2014. Ruben also plays ... a Melody Maker in CGCFAD tuning - which is dropped D tuning one full tone down...
"Rigged: Wintersun". MetalSucks.net. 30 July 2013. Retrieved 12 December 2013.
The Tallest Man On Earth - Topic (30 November 2014), The Sparrow and the Medicine, archived from the original on 13 December 2021, retrieved 4 March 2019
"A Brief History of Hawaiian Slack Key Guitar" (PDF). Dancing Cat Records. Retrieved 13 May 2014. ... C-G-D-G-B-E Tuning (often called "Keola's C", because it has been used most prominently by Slack Key guitarist Keola Beamer)