Salam (means Hello) :)

parsing output of a third party script, which was stored in a MySQL database, I encountered data structures almost like JSON, but in a triplets of:

key_type:key_length:key_name;
value_type:value_length:value_contents;

this is a example of it:

a:1:{
    s:5:"title";
    s:28:"<div>This is item title</div>";
    s:9:"permalink";
    s:31:"http://example.com/post-88.aspx";
    s:7:"content";
    s:31:"<div>This is item content</div>";
    s:4:"meta";
    a:1:{
        s:4:"tags";
        s:22:"these, are, some, tags";
    }
}

I just want to know is this a common standard structure or something conventional created by this script developers?