As you age, your eyes are going to get worse, that's just part and parcel of aging. When it comes time to have to get glasses to help you see both near and far, your doctor is going to recommend that you get bifocals. You may not want everyone to know that you have bifocals, so you may want to consider progressive lenses. But, you may know the difference between the two.
The lenses in your glasses aren't all designed the same from one point of your glasses to the next. They are designed so that they have a particular focal point. That focal point is the point where your eye is going to see the best and everything will be clearest. Multi-focal lenses have more than one of those points, which means that they are going to help you see at a variety of distances with the same clarity. Whether you choose bifocals or progressive lenses, you are still going to end up with multi-focal lenses.
Bifocals come in lined and unlined versions. They both have a particular area in your lenses that are set for the near vision that you need. With a lined version, that section is obvious, since there is a definite line between where far and near vision. With the unlined version, you are still going to get a definite area that has your near vision focal point. In order to switch between the focal points, you will have to move your eyes up and down. In the first few days, it may feel weird, but you will eventually get used to doing it and not even notice.
Progessive lenses are exactly that. The focal points progressively move from your far vision focal point to your near vision focal point. It can be a more gradual transition to the near distance point, and may give you a more in between point that may make it easier for you to see things that are just outside of the areas where you can see easily with either your near or far focal points, such as your computer screen or the dashboard of your car.
Having to have bifocals is pretty much a fact of life. Your eyes start to not focus as well the older you get. That means they need to have some help. Multi-focal lenses can help with that. Knowing the difference between bifocals and progressives will help you make the right choice. Talk to an optometrist at centers like Tamas EyeCare to learn more.