Strings are Immutable. StringBuilder is special case where the buffer size increases(doubles up every time when the length is in shortage),instead of creating new strings every time when an concatenation operation takes place on string.
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String a = "";
for (int i = 1; i < 100; i++)
{
a = a + "" + "Test"; //Improper Usage it would create 100 objects of strings
}
StringBuilder builder=new StringBuilder();
for (int i = 0; i < 100; i++)
{
//Proper Usage only buffer size increase
builder = builder.Append(a).Append(" ").Append("Test");
}
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