Acabo de guardar l'arxiu a la carpeta de l'ordinador.

Acabar de + infinitive is a very common Catalan structure meaning to have just done something.

So:

• acabo de guardar = I have just saved
• literally, it looks like I finish from saving, but that is not how it works in real usage

More examples:

• Acabo d'arribar = I've just arrived
• Acabem de menjar = We've just eaten

It is one of the most useful everyday patterns in Catalan.

Because in Catalan, present tense of acabar + de + infinitive is the normal way to express the recent past.

So even though acabo by itself is present tense, the whole expression means just did.

That is:

• acabo = I finish / I am finishing
• acabo de guardar = I have just saved

English does something similar in meaning, but with a different structure: have just saved.

Yes.

• He guardat l'arxiu a la carpeta de l'ordinador means I saved / I have saved the file in the computer folder
• Acabo de guardar l'arxiu... adds the idea that it happened just now

So the difference is mainly:

• he guardat = the action happened
• acabo de guardar = the action happened very recently

Because Catalan definite articles el and la usually shorten to l' before a vowel sound.

So:

• el arxiu becomes l'arxiu
• el ordinador becomes l'ordinador

This is called elision.

In this sentence:

• l'arxiu = the file
• de l'ordinador = of the computer

Notice that de l' is normal here. If the masculine article were not elided, you would often get del:

• del llibre = of the book
• but de l'ordinador = of the computer

The two prepositions do different jobs.

• a la carpeta tells you where the file was saved
• de l'ordinador tells you which folder it is: the folder of/on the computer

So:

• a often marks a destination, location, or place something is put
• de often shows possession, relationship, or specification

English often uses noun chains like computer folder, but Catalan commonly uses de:

• la carpeta de l'ordinador = the computer's folder / the folder on the computer

Catalan usually uses definite articles more often than English does with specific nouns.

So this sounds natural:

• l'arxiu
• la carpeta
• l'ordinador

In English, you might sometimes say saved file to computer folder in a shortened style, especially in menus or technical notes. In normal Catalan sentences, leaving out the articles here would usually sound unnatural.

Yes, for English speakers it often is.

In Catalan, carpeta means:

• folder
• sometimes file folder or binder, depending on context

It does not mean carpet.

For carpet, Catalan uses words like:

• catifa
• moqueta (depending on the kind of carpet)

So in computer language, carpeta is exactly the normal word for folder.

Because in Catalan, guardar commonly means to save, to keep, or to store.

In computer contexts, guardar is a very normal choice for save a file.

You may also see:

• desar = also used for save, especially in some varieties and interfaces

A learner may expect salvar because of English save, but salvar usually means to rescue or to save someone/something from danger. It is not the most neutral everyday choice for saving a computer file.

So:

• guardar un arxiu = very natural
• desar un arxiu = also natural in many places
• salvar un arxiu = much less standard/common for this meaning

They are:

• arxiu — masculine
• carpeta — feminine
• ordinador — masculine

That is why the full articles are:

• el arxiu → l'arxiu
• la carpeta
• el ordinador → l'ordinador

Knowing the gender helps you build other sentences correctly.

For example:

• un arxiu nou
• una carpeta nova
• un ordinador nou

A good English-friendly approximation is ar-SHEEW.

A few helpful points:

• the x in arxiu sounds like sh
• iu at the end forms a glide, roughly like yoo compressed into one syllable ending

So:

• arxiu ≈ ar-SHEEW

And a rough pronunciation of the whole sentence is:

• ah-KAH-boh deh gwar-DAR lar-SHEEW ah luh kar-PEH-tuh deh lur-dee-nuh-DOR

That is only an approximation, but it is good enough to get started.

Yes. This is a very normal, neutral word order in Catalan:

• Acabo de guardar
  • l'arxiu
    • a la carpeta de l'ordinador

It goes:

1. the verb phrase
2. the direct object
3. the place

You can move parts around for emphasis, but the version you have is the straightforward everyday order and a very good model to learn from.