What are Alkynes?
Alkynes are a class of organic, unsaturated hydrocarbons (contain Carbon and Hydrogen) that have a Carbon-Carbon triple bond.
You might commonly see them depicted like this, in Organic Chemistry:
You might also hear about Alkanes and Alkenes, as well as Alkynes. The difference is that Alkanes have a single bond between Carbon atoms, and Alkenes have a double bond between Carbon atoms.
I hope that helps!