地形图，是普通地图的一种，是按一定比例尺表示地貌、地物平面位置和高程的一种正射投影图。其基本特征是：
        （1）以大地测量成果作为平面和高程的控制基础，并印有经纬网和直角坐标网，能准确表示地形要素的地理位置，便于目标定位和图上量算；
        （2）以航空摄影测量为主要手段进行实地测绘或根据实测地图编绘而成，内容详细准确；
        （3）地貌一般用等高线表示，能反映地面的实际高度、起伏状态，具有一定的立体感，能满足图上分析研究地形的需要；
        （4）有规定的比例尺系列，如我国规定国家基本比例尺地形图系列为：1:1万、1：2.5万、1:5万、1:10万、1:20万(现已为1:25万) 、1:50万、1:100万，可以基本满足国家经济建设和军队作战指挥的不同需要；
        （5）有统一的图式符号，便于识别使用。
        此外，为保持地形图的现势性，还规定了定期更新。

Topographic map is a general map is based on a certain scale of that landscape, location and elevation plane features an ortho projection. Its basic characteristics are:
         (1) the results of the geodetic elevation, as plane and the control base and printed with latitude and longitude coordinates at right angles to networks and network elements can be accurately said that the topography of the location, easy to locate and map the target volume calculation;
         (2) aerial photography as the main means of measuring the field mapping or compilation based on maps from the measured, detailed and accurate;
         (3) the general topography with contour lines that reflect the actual height of the ground, ups and downs, and has a three-dimensional sense of the map to meet the needs of the terrain analysis;
         (4) the provisions of the scale series, such as the provisions of China's basic national topographic map series for scale: 1:1 million, 1:2.5 million and 1:5 million and 1:10 million and 1:20 million (now for the 1: 250,000), 1:50 million and 1:100 million, you can basically meet the needs of national economic construction and military operational command of the different needs;
         (5) a unified schema symbols, make it easier to identify the use.
         In addition, topographic maps in order to maintain the current potential, and also provides a regularly updated.