什么是 json ？
在 WEB 应用系统开发以及数据分析中经常遇到 json 数据格式的文件，如下示意：
{
"paramz": {
"feeds": [
{
"id": 299080,
"oid": 288342,
"category": "article",
"data": {
"subject": "视频直播：习近平马英九会面",
"summary": "两岸领导人习近平、马英九在新加坡会面",
"cover": "/Attachs/Article/288342/56a263bcab4a4c55b0bef0528ce880b6_padmini.JPG",
"pic": "",
"format": "video",
"changed": "2015-11-07 14:35:22"
}
},
{
"id": 299076,
"oid": 288340,
"category": "article",
"data": {
"subject": "荔枝新闻3.0：不止是阅读",
"summary": "江苏广电旗下资讯类手机应用“荔枝新闻”于近期推出全新升级换代的3.0版。",
"cover": "/Attachs/Article/288340/3e8e2c397c70469f8845fad73aa38165_padmini.JPG",
"pic": "",
"format": "txt",
"changed": "2015-09-22 16:01:41"
}
}
],
"PageIndex": 1,
"PageSize": 20,
"TotalCount": 53521,
"TotalPage": 2677
}
}
这种格式的数据有什么特点，代表什么含义，如何使用呢？