
Alkanes are a group of saturated hydrocarbons. Examples - methane, ethane, propane, butane, pentane, etc.
Alkenes are a group of unsaturated hydrocarbons having a least one double bond. Examples - ethene, propene, butene, pentene, and so on.
Alkynes are a group of unsaturated hydrocarbons having a least one triple bond. Examples - ethyne, propyne, butyne, pentyne, etc.
Oic acid is the suffix used for carboxylic acids in organic chemistry. Examples - ethanoic acid, butanoic acid, etc.