When traveling within a country, it’s important to remember that there are almost always a few different ways to get to where you’re going. If you’re in a city, there are probably cabs, trains, and maybe busses. In a more rural area, you might have to be a little creative–sometimes you can rent bikes or travel via van. Just getting from place to place gets expensive quickly, so it’s important to plan your budget accordingly.
There’s nothing wrong with exclusively taking cabs, but it can be costly. In some places, cabs aren’t metered; rather, you and the driver are supposed to arrange a price (through haggling) before the trip. Make sure you know the customs before you arrive.
I’m a strong advocate of public transport because of the low cost. It can be a little bit daunting to walk into a crowded train station and get a ticket when there’s no signage in English, but chances are, you’ll figure it out. You’re resourceful, after all. Another bonus of traveling this way is that you get more than a tourist’s perspective of wherever you are.
But remember, the most important thing is often your comfort level. If you sense that you may be in a shady part of town, or it’s late at night, and you just need to get somewhere without hassle, a cab may be best for you.