Let’s start off with the similarities. Both ballpoint pens and rollerball pens use a ball and socket mechanism. With gravity, the ink is forced down through the ink reservoir and onto the rolling ball. This technology is similar to the mechanisms you see being used on roll-on antiperspirants or rollerball perfumes.
The pen you probably have seen most in your life is the ballpoint pen. These are the pens you will get from banks and doctor’s offices. One of the biggest advantages in using a ballpoint pen is that these pens don’t easily dry out due to their oil-based ink, which is thicker than the liquid or gelled ink used in their rollerball counterparts. Furthermore, the ink in the ballpoint pen doesn’t smudge due to it’s fast drying time and it does not bleed through paper either. These are some of the reasons it is preferred for everyday use around schools and workplaces. It is also usually less expensive than a rollerball. Beyond this, since the ink is more viscous, it also comes out slower which means the cartridge has a longer lifespan and would require less refills. However, the thicker ink also means that it takes more pressure to write with a ballpoint than a rollerball which can become tiring after long spans of time. Overall, though, these pens are a great pick for anyone who’s looking for a reliable pen that is stylish and easily portable.