The lines that intercept latitude lines are lines of longitude.
The latitude lines printed on a map will depend on the scale of the map. A map of the Earth will probably have latitude lines printed every 15 or 30 degrees; a map of the United States will have latitude lines printed every 5 or 10 degrees.
On a map, longitude lines go up and down, AKA vertically. Latitude lines are horizontal lines on a map.
longitude
Parallel lines found on a map correspond to latitude.
The lines that are perpendicular to the latitude lines on a map are called longitudinal lines. There are 24 of them, each representing 15 degrees of change.
There can be various lines on a map, but the ones you are probably thinking of are 'latitude' and 'longitude'.
Lines of latitude on a polar projection map radiate outward from the center towards the edges of the map. On a polar projection map, the North Pole is typically at the center, while lines of latitude move southward towards the map edges.
grid lines of longitude and latitude
They are the horizontal lines on a map.
Not all maps show latitude and longitude. On those that do some have horizontal lines indicating where lines of latitude lie, and on the right and left margins of the map these lines will have the latitude they represent marked. Then on some maps the lines are missing but the notations in the margin show where the lined of latitude should be.
Latitude and longitude
A map with parallel lines of latitude and longitude is known as a Mercator projection map. This type of map is often used for navigation purposes due to its representation of straight lines of latitude and longitude, making it easier to measure distances and plot courses. However, the Mercator projection distorts the size of landmasses, especially near the poles.