Each forms equal number of isomers for a given compound

If in a compound, one is present, then so is the other

Both are included in stereoisomerism

They have no similarity

3

2

4

6

(+) tartaric acid and meso tartaric acid are tautomers

(+) tartaric acid and meso tartaric acid are diastereomers

(+) tartaric acid and (−) tartaric acid are diastereomers

(+) tartaric acid and meso tartaric acid are enantiomers

Enantiomers

Constitutional isomers

Diastereomers

Different conformations of the same compound

1,2−dichloro−1−pentene

1,3−dichloro−2−pentene

1,1−dichloro−1−pentene

1,4−dichloro−2−pentene