Question

what is carbon carbon single bond ?

Answer 1

A carbon–carbon bond is a covalent bond between two carbon atoms. The most common form is the single bond: a bond composed of two electrons, one from each of the two atoms. The carbon–carbon single bond is a sigma bond and is formed between one hybridized orbital from each of the carbon atoms

Answer 2

Now we all know that carbon has these two of the very special properties namely catenation and tetravalency
Catenation meaning that carbon can make hundreds and thousands of bonds in a chain or ring with other carbon atoms alongside.
But what does a single bond mean?
Well any bond is made between two atoms when each share one of their electron of their outermost shell (specifically high energy orbital)
and form a pair of electrons which is known as a covalent bond.
Thus a single bond means that only one pair of electrons has been made that is only one electron given by each atom of their own.
Thus, carbon can give 4 electrons or rather I would prefer to say that carbon atom can share 4 electrons of it's outermost shell and thus,.when any two carbon atom share one electron each and form a pair of electrons , this is known as single bond.
Similarly, if the carbon atoms give two electrons each they form two pairs of electrons and thus giving a double bond and similarly if each carbon atom gives three electrons each, then they form what is called a triple bond.

Hope this helps you !
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