Nginx - root versus alias, for serving single files?

Question

After many hours getting nginx to serve single files such as robots.txt (hint: clear your browser cache each time), I wound up with two different ways, one using the alias directive, and one using the root directive, like so:

location /robots.txt { alias /home/www/static/robots.txt; }
location /robots.txt { root /home/www/static/;  }

Is there any functional difference between the two? Or security issues? Any conflicts with other directives? (Both seemed fine with another /static location). Or any reason to pick one over the other?

Note - I didn't use both at the same time :) Rather I tried each, one at a time, and both worked. I'm not asking how they both interact together in the same file, but which one would be better to use.

Answer 1

Well, these two directives are slightly functional different because you do not use exact match in the latter case. So, /robots.txt1111 will match your second location too.
location =/robots.txt { root /home/www/static/; } is an exact functional equivalent of your first directive.