In the age of information, recent researches and applications are brought several innovations to our daily lives in the fields of Internet and communication technologies. Internet becomes an environment that is connectable not only by people but also by things. Today, almost every gadget in our daily life is able to connect to Internet. Such evolution of Internet generated the Internet of Things (IoT) concept. Successful applications of IoT have been demonstrated in many fields. However, IoT is still at its infancy stage. IoT envisions a future in which digital and physical entities can be linked, by means of appropriate information and communication technologies, to enable a whole new class of applications and services. In this article, we presented a survey of concept, characteristics, technologies, applications and research challenges for IoT which have been developed and became popular in recent years. We also analyzed and discussed the open research problems in IoT.