If A and B are two sets, and every element of set B is also an element of set A, then B is called a subset of A and we write it as B ⊆ A or A ⊇ B.

Example: 1

Set A = {john,mary,tom,tony}

Set B = {john,tony}

Since every element of Set-B is present in Set-A, therefore B is called a subset of A.

Example: 2

Set A = {john,mary,tom,tony}

Set B = {john,Tony}

Since Tony in Set-B is having capital(T) and Set-A is having samll(t) in Set-A, means all the element of set-B is not present in set-A, therefore B is not a subset of A.

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