交通信號燈是指揮(hui)交通(tong)(tong)運行(xing)的(de)信號燈，一般由紅燈、綠燈、黃燈組成(cheng)。紅燈表(biao)(biao)示禁止通(tong)(tong)行(xing)，綠燈表(biao)(biao)示準許通(tong)(tong)行(xing)，黃燈表(biao)(biao)示警示。

    交通信(xin)號(hao)(hao)燈(deng)分為：機(ji)動車(che)信(xin)號(hao)(hao)燈(deng)、非機(ji)動車(che)信(xin)號(hao)(hao)燈(deng)、人行橫道(dao)信(xin)號(hao)(hao)燈(deng)、方向指示(shi)(shi)指示(shi)(shi)燈(deng)（箭頭信(xin)號(hao)(hao)燈(deng)）、車(che)道(dao)信(xin)號(hao)(hao)燈(deng)、閃光警告信(xin)號(hao)(hao)燈(deng)、道(dao)路與(yu)鐵(tie)路平面交叉(cha)道(dao)口信(xin)號(hao)(hao)燈(deng)。

    在(zai)十字路口，四面都(dou)懸(xuan)掛著紅(hong)(hong)、黃(huang)、綠、三(san)色交(jiao)通(tong)(tong)信號(hao)燈(deng)(deng)(deng)，它是(shi)不(bu)出聲的(de)(de)“交(jiao)通(tong)(tong)警察”。紅(hong)(hong)綠燈(deng)(deng)(deng)是(shi)國際(ji)統一的(de)(de)交(jiao)通(tong)(tong)信號(hao)燈(deng)(deng)(deng)。紅(hong)(hong)燈(deng)(deng)(deng)是(shi)停(ting)止信號(hao)，綠燈(deng)(deng)(deng)是(shi)通(tong)(tong)行(xing)信號(hao)。交(jiao)叉路口，幾個方向來的(de)(de)車(che)都(dou)匯集(ji)在(zai)這兒，有(you)的(de)(de)要直(zhi)行(xing)，有(you)的(de)(de)要拐彎，到底讓誰先(xian)走，這就是(shi)要聽從紅(hong)(hong)綠燈(deng)(deng)(deng)指揮(hui)。紅(hong)(hong)燈(deng)(deng)(deng)亮(liang)，禁止直(zhi)行(xing)或(huo)左轉彎，在(zai)不(bu)礙行(xing)人和車(che)輛(liang)情況下，允許車(che)輛(liang)右轉彎；綠燈(deng)(deng)(deng)亮(liang)，準(zhun)許車(che)輛(liang)直(zhi)行(xing)或(huo)轉彎；黃(huang)燈(deng)(deng)(deng)亮(liang)，停(ting)在(zai)路口停(ting)止線或(huo)人行(xing)橫道線以內，已經繼續(xu)通(tong)(tong)行(xing)；黃(huang)燈(deng)(deng)(deng)閃(shan)爍時(shi)，警告車(che)輛(liang)注意安全。