Meteorologists use many symbols to describe the different weather conditions. An area of high pressure is denoted by a big "H" and an area of low pressure is denoted by a large "L". (For more information on what type of weather these areas of pressure cause, check out the WX 101: Weather Systems). Connected to the low pressure system you find your fronts. A warm from is a red line with small red bubbles connected to it. A cold front is a blue line with small blue triangles connected to it.
There are also weather symbols used to describe a weather observation system. The small circle in the middle of the observation plot describes current cloud cover. Connected to that circle is the wind barb. This explains which direction the wind is blowing, and the current wind speed. To the left of the wind/cloud circle is a weather symbol. This explains what form of precipitation is falling at that location. The line of numbers to the left of the wind/cloud circle includes current temperature, visibility, and dew point. The line of numbers to the right include barometric pressure, recent pressure trend, and amount of precipitation that has fallen in the last six hours.