"out" versus "outside" and "in" versus "inside"
I cannot distinguish the difference between "out" and "outside". The same happens with "in" and "inside". I would like to know your opinions. Thank you.
7 Answers
Is Ana at home?
No, she's just gone out = she's just left (shopping, to work, to school etc.)
No, she's just gone outside (she's in the garden or in the playground nearby).
Okay, with absolutely no reference to anything except a moment's reflection....
Sometimes there is no difference. I say to my dog "Do you want to go out?" And sometimes "Do you want to go outside?" There is a tag in my sweater." sounds as correct as "There is a tag inside my sweater."
On the other hand, sometimes only one is correct. You can talk about the outside of a box, but not the "out" of it. A sign can be on the outside of a building, but not the "out" of it.
Seems like all the cases where you need "the" must be inside/outside... and they tend to refer to a physical part of the object in question.
In every other case I can call to mind they seem to be interchangeable.
Another distinction is between "out" purely in the sense of not in some particular place/building but with no implication about where (even if it's inside some other place/building) versus "outside" meaning not in any building (under open skies). Thus: "We're going out tonight." (perhaps to spend the time inside a cinema/restaurant/night club) as contrasted with "I'm going outside." (to walk the dog, look at the stars, breathe the smog). In this case, "out" is the more inclusive term (one can also go out to refer to any of these activities).
There are also uses that seem to parallel the traditional "fuera"/"afuera" distinction {having to do with motion] (but, apparently, that distinction is no longer consistently made in Spain (and in other Spanish-speaking countries, may have disappeared even earlier).
I agree with Valerie. I would use outside in terms of a relative physical position. Out seems more natural to use in the context of action.
I like your questions about the nuances of language. Thanks.
All my comments are just based on being a native speaker that likes to think about language.
There is a tag in my sweater." sounds as correct as "There is a tag inside my sweater."
Valerie, I think that you are referring to the inside of the sweater in the two cases.
Other very different thing would be when you are talking about the tag when it is on the sweater. Is that?
Sorry, I have just guessed the exact meaning of tag. Then, the latter sentence does not make sense.
Both words have multiple meanings as adjectives, adverbs, nouns, and prepositions and out can also be used as a verb. This complicates things too much to give a simple answer, or even one limited to a single page. Their meanings overlap in some cases, but many times they don't. The various meanings tend to carry over into the various word forms in a predictable way, just like other multipurpose words.
I know you can look the word up but out is "fuera" and outside is "exterior". Is there another word or words that can be used in these cases? I was also wondering if "fuera" is used to refer to a player in baseball being "out" or a player in general being sent "out" of a game? Just a side thought. 
