Slider windows are considered a more modern style of window becoming popular with the advent of weather resistant materials.
Double Slide Window
Sliding / Gliding Window Details:
Sliding window can also be referred to as gliding or slider windows. A sliding window has two sashes with at least one that slides horizontally past the other. While one sliding sash and one fixed sash is the most common option it is possible to purchase windows which allow both sashes to slide.
While sliding windows are not as effective as modern casements at sealing out air, they still do a much better job than older windows that they are replacing and are known for their ease of operation. Sliding windows are a better choice for homes in warm/dry parts of the country as their seal will not be as crucial as in a wet and cold area
Sliding windows may be a good choice for areas where an outward opening window (casement or awning) might get in the way such as decks, walkways, etc...