Bitcoin is the heart of all coins not only this bitcoin is the heart of coin market, total market disturbed with the move of the bitcoin, if it shine all other coins shine and if it shows some down ward trend all other coins cool down and slide down ward, this is reason it called the heart of all coins.
That is tru and also the heart of every body because it gives us opportunities and we can do transaction too insuch as easy way to go around. Altcoins are might useful though it has small value but it will keep growing as the days passing by all around just believe on it.