Spanish uses the Latin alphabet as it has come to be known in Europe (including a "j" after "i" and a "y" before "z"). "K" and "W" are included, but are used mainly for foreign-origin words (like kilograma and waltzer). Traditionally, four additional letters were added: The "CH" after "C" (pronounced /ʃ/), the "LL" after "L" (pronounced /ʎ/), the "Ñ" after "N" (pronounced /ɲ/), and the "RR" after "R" (pronounced with a trill of tongue). Since 1994 these letters have not been used for alphabetization (that is, words beginning with "ch" come between "ce" and "ci" rather than after "cz").
In spoken Spanish, words ending in a vowel, "n" or "s" are stressed on their penultimate syllable (example: niveles (ni-VEL-es) - levels). All other words are by default stressed on the ultimate syllable (example: nivel (ni-VEL) - a level). Any other stress requires an acute accent, as in antepenúltimo (antepenultimate), or lápiz (shift to penult) or comí (shift to ultimate). The only real trick is in knowing when there is a separate syllable when two vowels come together, and when there is not. The rule is fairly simple: Two strong vowels (a, e, o) make two syllables (tarea, rodeo). A strong vowel and a weak vowel (i or u) make a diphthong, that is, one syllable with a combination vowel sound (lengua, causa, Juana). For that reason, "guion" (ghee-ON) is stressed on the last syllable, but does not hava an accent mark. It is a one syllable word.
Stress goes to the strong vowel if the syllable is accented. Two weak vowels also create a diphthong, with the stress on the second vowel, as in "idiota." There are only a few exceptions to the rule, and accent marks are used to note them (as in "flúido").
The diacritical marks of Spanish are the acute accent (á) and the tilde over the "n" thus: "ñ". The acute accent is used in three circumstances. Most often it indicates a shift of the normal rules of stress in a word, such as "habló" (ah-BLO - she spoke) instead of "hablo" (AH-blo - I speak). It is also used to divide letters that would otherwise be a diphthong, such as "sería" (say-RI-a - "it would be") instead of "seria" (SAY-rya - "serious"). Finally, it is used to distinguish between two words that are spelled the same, but mean different things, as in "más" (more) and "mas" (but). This latter rule also applies to distinguish between a relative pronoun and an interrogative pronoun, as in "que" (that) and ¿qué? (what?). Beyond that, Spanish uses the superscrip "a" and "o" to abbreviate ordinals that need to agree in gender with the noun being counted. Exclamation marks and question marks are inserted upside-down at the beginning of the exclamation or question, and right-side up at the end.
The letters "b" and "v" have come to be indistinguishable in most spoken versions of Spanish. In Spain the "b" is called "be" (pronounced "bay") and the "v" is called "uve" (pronounded "OO-bay"). In other places, "b" is sometimes called "b grande" and "v" is called "v pequeña" or "v chica," or even "b de burro" and "v de vaca." Spanish speakers who are not well-practiced in writing will frequently confuse these two letters.
Likewise, it is sometimes not clear whether a word is spelled with an "s" a "z" or a "c" before "i" or "e." A person unaccustomed to writing might spell "atrasó" with a "z" for example, "atrazó." In the same way, someone might write "resar para mi" (to pray for me) instead of "rezar," which is correct, or "orasión" (prayer or sentence) for "oración."
The other orthographic complication involves the sound of a hard "c" and the retroflex fricative "j". In Spanish, "c" is used (rather than "k") for the hard "c" sound, except that "c" is soft before "i" and "e." Thus, the letter combination "qu" is used for the hard "c" sound before "i" and "e." For example, compare "escuela" (es-KWAY-la -- school) and "esquema" (es-KAY-ma -- system or scheme). "Escuela" also shows that the "qu" sound in English is written as "cue" in Spanish and pronounced "kway." In the same vein, "g" is a hard "g" everywhere except before the vowels "i" and "e." Then it is soft. "gu" is used to make the "g" a hard sound before those to vowels, when required. The soft "g" is pronounced just like a "j." Thus, "Jorge" (George) has two identical soft "g" or "j" sounds, one spelled with a "j" before the "o" and one with a "g" before the "e." On the other hand, "to guide" in Spanish is "guiar" (gee-AR). It begins with the hard "g" sound, but requires the "gu" combination to prevent the "g" from being soft before the "i." Compare this with "girar" (to turn or spin), which has the soft "g" (the "j" sound) as in "Jorge." Finally, when the "u" in "gu" is supposed to be pronounced, that is, when it is not silent and serving just to harden the "g" before "i" or "e," a dieresis (two dots over the "u") is employed. For example, "güero," a Mexican term for fair-skinned or blond, is pronounced "UE-ro." The "u" makes the "g" almost disappear, though technically, it should be there as a hard "g." If the dieresis were not there, the word would be pronounced "GAY-row."
Another pitfall is the confusion of double-ell ("ll") and "y" in countries that do not give the "ll" its own sound. (In other words, in places where "Gallo" (rooster) is pronounced "GUY-oh".) The Italian name Mirella is, in fact, spelled "Mireya" in many parts of the Spanish-speaking world. A word like "pollo" (chicken) will sound very much the same as the two last syllables of the word "apoyo" (support).
With the exception of these four possible spelling troublemakers, which commonly cause errors for younger school children and people of limited literacy, Spanish is written exactly as it is pronounced. Unlike English, which has nearly two dozen vowels but only 5 or 6 letters with which to spell them, Spanish bears a fairly close one-to-one relationship between its letters and its phonetic sounds. A couple of minor exceptions to this simple rule still persist. Centuries ago, the "j" was spelled with an "x" in many contexts, and it has persisted in geographic names, like "México." Additionally loan words, many from English, are spelled in the foreign manner, but pronounced more colloquially. An example is "flash drive" or simply "drive." Because the "sh" is not a Spanish consonant in most accents, the word "flash" tends to be pronounced "flacs." Another example is "meeting," which is pronounced "mitin" (MEE-teen). It is also spelled that way often in newspapers.
A couple of minor conventions persist in written Spanish. The word for "or" or "either/or" is "o" or "o/o." To prevent mistaking it for a zero, it bears an accent when numbers are involved or whenever there is a possibility of confusion. Another old-fashioned convention is the omission of accent marks from capital letters, though modern standards consider it to be an orthographical mistake not to use them.