There are seven strong acids in existence. A strong acid is an acid whose component ions completely dissociate when the acid is dissolved in water. In the case of acids, one of the dissociated ions will always be a hydrogen cation (\(H^{+}\)). The chemical formulas and names of these acids are listed below:
\(HCl\) Hydrochloric Acid
\(HBr\) Hydrobromic Acid
\(HI\) Hydroiodic Acid
\(HNO_3\) Nitric Acid
\(H_2SO_4\) Sulfuric Acid
\(HClO_4\) Perchloric Acid
\(HClO_3\) Chloric Acid
All other acids are known as weak acids because their ions only partially dissociate when the molecules are dissolved in water. If you are trying to neutralize a base, a strong acid in many cases will be more efficient since the acid can only react with the base once the ions are dissociated, and the more complete this dissociation is, the faster the process is since there are more ions to use. Note that some weak acids are more effective at this task than others; they all have varying strength, but it is improper to call any of these strong acids since the terminology then becomes ambiguous.
Resource: Chemistry: The Central Science 10th Edition, Brown, LeMay, Bursten