The compound having same molecular formula but different properties are said to be isomers of each other and this phenomena is called isomerism.

Compounds of carbon which have same molecular formula but different structures this phenomenon is known as isomerism
It is the phenomena by which carbon can form bonds in long chains or branched chains.

Carbon chain can be branched. So they form two or more compounds which have same chemical formula but different structure such compounds are known as isomers and their property is isomerism
When two compound having same molecular formula but differnt arrangement

Isomerism is the phenomenon whereby certain compounds, with the same molecular formula, exist in different forms owing to their different organisations of atoms. The concept of isomerism illustrates the fundamental importance of molecular structure and shape in organic chemistry.

The phenomennon of covalant compounds in which their structure differintiates sometimes leading to dofference in properties is called isomerism

Same molecular formula but different behavior
Isomerism is a phenomenon in which two or more compounds has the same chemical formula but show different properties because of different structural arrangement
Can u explain it in detail
It is a phenomena in which molecules have a same structural formula but different dimensions