Which type of window operates similarly to jalousie windows but typically consists of one large or two medium-sized glass panels?

The question is asking about a type of window that operates similarly to jalousie windows but is typically made up of one large or two medium-sized glass panels. The correct choice is awning windows.

Awning windows are hinged at the top and open outward, allowing for ventilation while still protecting against rain since they can be opened when it’s raining. This operating mechanism is reminiscent of jalousie windows, which consist of multiple slats that can be opened for airflow, though jalousie windows typically have more individual slats than the larger panels of awning windows.

The other types of windows mentioned do not match the description as closely:

• Horizontal sliding windows open sideways on tracks, but they do not have the same hinging feature that allows for an outward opening like awning windows.
• Casement windows also open outward but typically consist of a single panel and are hinged on one side rather than on the top.
• Projected windows is a broader term that might include various window types but does not specifically describe the function and structure akin to jalousie windows.

Thus, the structural characteristics and operational function of awning windows distinguish them as the correct answer in this context.