Aw

...yes, perhaps you should have looked at the tags. Hopefully someone else did and all will be well.
Whilst it's very tempting to adopt a nice dog that you find, please don't ever do so without trying very hard to find the owners first! They could be distraught at losing their dog and desperate to find it.
By all means take care of a stray dog - that can sometimes be better/safer than giving a dog to a shelter - but remember that the owners may want to reclaim him so you must do your best to find them.