Parallels of Latitude:
- Parallels of latitude are imaginary lines that run parallel to the equator and are used to measure distances north or south of the equator.
- They are also called lines of latitude.
- The equator is the starting point for measuring latitude and is assigned a value of 0 degrees.
- The latitude increases as one moves northward from the equator and decreases as one moves southward.
- The maximum latitude is 90 degrees at the North Pole and the South Pole.
- Each degree of latitude is further divided into 60 minutes and each minute into 60 seconds.

Meridians of Longitude:
- Meridians of longitude are imaginary lines that run from the North Pole to the South Pole and are used to measure distances east or west of the Prime Meridian.
- They are also called lines of longitude.
- The Prime Meridian, passing through Greenwich, England, is assigned a value of 0 degrees.
- The longitude increases as one moves eastward from the Prime Meridian and decreases as one moves westward.
- The maximum longitude is 180 degrees, halfway around the globe.
- Each degree of longitude is further divided into 60 minutes and each minute into 60 seconds.

Key Differences:
1. Orientation: Parallels of latitude run parallel to the equator, while meridians of longitude run from the North Pole to the South Pole.
2. Measurement: Parallels of latitude are used to measure distances north or south of the equator, while meridians of longitude are used to measure distances east or west of the Prime Meridian.
3. Starting Point: The equator is the starting point for measuring latitude (0 degrees), while the Prime Meridian is the starting point for measuring longitude (0 degrees).
4. Maximum Values: The maximum latitude is 90 degrees at the North Pole and the South Pole, while the maximum longitude is 180 degrees, halfway around the globe.
5. Division: Each degree of latitude is further divided into 60 minutes and each minute into 60 seconds, similarly, each degree of longitude is further divided into 60 minutes and each minute into 60 seconds.

Summary:
Parallels of latitude and meridians of longitude are important concepts in geography. Parallels of latitude run parallel to the equator and measure distances north or south of it, while meridians of longitude run from the North Pole to the South Pole and measure distances east or west of the Prime Meridian. The equator and the Prime Meridian serve as the starting points for measuring latitude and longitude, respectively. The maximum latitude is 90 degrees at the poles, and the maximum longitude is 180 degrees, halfway around the globe. Each degree is further divided into minutes and seconds for precise measurements. Understanding these concepts is essential for locating places on maps and understanding global positioning.