URI = ( absoluteURI | relativeURI ) [ "#" fragment ] absoluteURI = scheme ":" *( uchar | reserved ) relativeURI = net_path | abs_path | rel_path net_path = "//" net_loc [ abs_path ] abs_path = "/" rel_path rel_path = [ path ] [ ";" params ] [ "?" query ] path = fsegment *( "/" segment ) fsegment = 1*pchar segment = *pchar params = param *( ";" param ) param = *( pchar | "/" ) scheme = 1*( ALPHA | DIGIT | "+" | "-" | "." ) net_loc = *( pchar | ";" | "?" ) query = *( uchar | reserved ) fragment = *( uchar | reserved ) pchar = uchar | ":" | "@" | "&" | "=" | "+" uchar = unreserved | escape unreserved = ALPHA | DIGIT | safe | extra | national escape = "%" HEX HEX reserved = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" extra = "!" | "*" | "'" | "(" | ")" | "," safe = "$" | "-" | "_" | "." unsafe = CTL | SP | <"> | "#" | "%" | "<" | ">" national = <any OCTET excluding ALPHA, DIGIT, reserved, extra, safe, and unsafe>Η χρήση τους επιτρέπει τον προσδιορισμό άλλων σελίδων τοπικά, σε άλλα μηχανήματα, καθώς και ερωτήσεων:
http://kerkis.math.aegean.gr/~dspin/ http://www.altavista.com/cgi-bin/query?pg=q&text=yes&q=link%3akerkis%2emath%2eaegean%2egr%2f%7edspin+%2dhost%3akerkis%2emath%2eaegean%2egr&stq=10&c9kΣημαντικά προβλήματα ασφάλειας που μπορούν να προκύψουν είναι τα παρακάτω: