This is the 4635th most frequent Swedish word.
alberto
"Alberto" is not a Swedish word; it is typically a masculine given name of Spanish or Italian origin.
Here, 'Alberto' is used as a proper noun referring to a person's name.
Alberto är min vän från Italien.
Alberto is my friend from Italy.
In this case, 'Alberto' is mentioned as the artist's name, again used as a proper noun.
Jag såg en tavla målad av Alberto.
I saw a painting made by Alberto.
This sentence uses 'Alberto' as the name of a person being directly spoken about.