什么是锚段？锚段有哪些作用？
["1\u5728\u533a\u95f4\u6216\u7ad9\u573a\uff0c\u6839\u636e\u4f9b\u7535\u548c\u673a\u68b0\u65b9\u9762\u7684\u8981\u6c42\uff0c\u5c06\u63a5\u89e6\u7f51\u5206\u6210\u8bb8\u591a\u673a\u68b0\u72ec\u7acb\u7684\u5206\u6bb5\uff0c\u8fd9\u79cd\u72ec\u7acb\u7684\u5206\u6bb5\u79f0\u4e3a\u951a\u6bb5\u30022\u951a\u6bb5\u7684\u4f5c\u7528\uff0c\u7f29\u5c0f\u4e8b\u6545\u8303\u56f4\uff0c\u7f29\u5c0f\u505c\u7535\u68c0\u4fee\u8303\u56f4\uff0c\u4fbf\u4e8e\u52a0\u8bbe\u8865\u507f\u88c5\u7f6e\uff0c\u4fbf\u4e8e\u5b9e\u73b0\u7535\u5206\u6bb5"]