The air masses separated by a front usually differ in temperature and humidity. Cold fronts may feature narrow bands of thunderstorms and severe weather, and may on occasion be preceded by squall lines or dry lines. Warm fronts are usually preceded by stratiform precipitation and fog.
https://en.wikipedia.org/wiki/Weather_front
A warm front is the leading edge of a warmer air mass coming in to replace a cooler one. The general direction in which warm fronts move in North America is from the southwest to the northeast. Since the air temperature increases as a warm front moves in, the air mass is able to hold more moisture and thus brings warmer and more humid characteristics with it.
http://comingbackalive.com/fronts.html
A weather front is a boundary separating two masses of air of different densities, and is the principal cause of meteorological phenomena. In surface weather analyses, fronts are depicted using various colored triangles and half-circles, depending on the type of front.
https://en.wikipedia.org/wiki/Weather_front
The four types of fronts change the weather on Earth. A warm front  brings warm, humid air and a cold front brings dry, cool air. A  stationary front does not move and have …winds parallel to the  front. An occluded front occurs when cold air overtakes warm air. 7 people found this useful.
http://www.answers.com/Q/What_do_weather_fronts_bring
Just as the name implies, a stationary front occurs when an air mass stops moving, returning to a cold front or warm front once it is set in motion again. Since the front is the boundary between two different air masses, it is represented on a map by alternating solid blue and red lines. On the lines, there are blue triangles pointing towards the warmer air and red semi-circles pointing towards the colder air.
http://comingbackalive.com/fronts.html
A Cold Front has Cold Air, that means you can expect a Temperature drop from this front. Most of the time, when a Cold Front passes over warm areas, you can expect storms to p…op up along this front. A cold front will usually bring cooler weather with a sharp change  in wind direction and clearing skies.
http://www.answers.com/Q/What_do_weather_fronts_bring
Weather fronts mark the boundary or transition zone between two air masses and have an important impact upon the weather. Weather fronts mark the boundary between two air masses, which often have contrasting properties. For example, one air mass may be cold and dry and the other air mass may be relatively warm and moist.
http://www.metoffice.gov.uk/learning/learn-about-the-weather/how-weather-works/weather-fronts
What is a weather front? A front is simply the boundary between two air masses. It can be thought of as the front line in a battle where the warm air represents one side and its 'enemy', the cold air, the other side.
http://www.metoffice.gov.uk/learning/learn-about-the-weather/how-weather-works/weather-fronts
Cold fronts and occluded fronts generally move from west to east, while warm fronts move poleward. Because of the greater density of air in their wake, cold fronts and cold occlusions move faster than warm fronts and warm occlusions.
https://en.wikipedia.org/wiki/Weather_front
Similar to the warm front, a cold front is the leading edge of colder air coming in to replace warmer air.These cold fronts tend to move from northwest to southeast bringing cooler temperatures and dryer air.
http://comingbackalive.com/fronts.html
what do cold fronts bring
Cold fronts bring cooler temperatures and dryer air.