Subway is the best transportation tool for traveling in Manhattan. Why? It's being known as one of the worst systems, in term of security and efficiency, etc. Similar to the public order of the city, it has been improved sharply in the recent years. I found it was safe for single traveler like me. If you really concern safety, just choose a car with patrol or scan through the cars before getting on. Just a note that some beggars will take subway on weekends morning.
The network there is very comprehensive. As it almost covers most tourism spots, it's very convenient to travel around. Another advantage is subway can save you from losing valuable time in traffic jam. Cost is very important too. Buy one-day pass if you will consume subway services 4 times or more a day. Or buy 7-day pass for longer stay.
Yet, the over hundred-year-old system is aging. Thus, lots of rejuvenation works often take place on weekends, like re-routing. So, don't forget always take a subway map with you in case you have to change your transportation plan.
Some subway stations are decorated in line of famous landmarks of its location. This cute elephant tile reflects the American Museum of Natural History is around.
Bus is also a low priced transportation tool. It may not be very convenient for those who are not familiar with the city. Also, it is easily caught by congestion during peak hours.
Alternatively, limousine or car rental services are available in Manhattan. This limousine with 10 pax capacity was hired by my friend on wedding day. It does look cool for big occasions. For long distance travel (between Manhattan and New Jersey) at night, the rate was reasonable though not cheap. I felt very satisfied with the services as it was very reliable and safe. I didn't prefer cab because my friends and me once met a dishonest driver. Next, the drivers compete crazily to get customers that endanger others' lives.
Sightseeing bus services probably suitable for tourists who wanna visit tourism spots door to door. But quite expensive for those with limited and money.
