Explanation of the word "se"
Could someone please give me a little more insight on the word "se". Like when, where, and why I should use it.
6 Answers
Se has a few uses in Spanish.
The first and most common being as a reflexive pronoun, ie. He shaves himself -> "El se afeita".
Because Ustedes and Usted both use the pronoun 'se', it can refer to themselves/theirselves OR eachother -> 'Ellos se aman' could mean 'they love themselves' OR 'they love eachother'. Context is the only way to differentiate here.
'Se' can also replace 'le', 'la', 'les', 'las' as an indirect object pronoun in the case that there is also a direct object pronoun present ('lo', 'la', etc.) For example: If I wanted to say 'he throws it' I could say 'la tira' (referring to la balón).
If i wanted to say 'he throws the ball to him' I could say 'le tira la balón (a él)'. BUT if I wanted to say 'he throws it to him' I would have to say 'se la tira'
Also, be sure to differentiate between se and sé, which is the first person singular present indicative of the verb saber.
I hope I haven't made any mistakes and have explained clearly.
I remember reading a post that Lazarus wrote where he detailed a laundry list of uses for "se." I thought that it might have been a reference article, but I didn't find it there. Do you possibly have the link to this article qfreed (we all know that you - Izanoni1 4 hrs ago
I've looked for it too, and finally.... TADAAA! Transitive and intransitive constructions: use of "se"
This is not a simple question.
Se is a reflexive pronoun (3rd person, singular and plural)
If you look up a verb in our dictionary, you will see that some of them are listed as pronominal. (as you can guess from the name that just means that they can be used with a pronoun) Including this pronoun changes the verb's (to a degree) meaning from when it is used without the pronoun. You will see the verb listed with se after it to show that the definition to be given is when the verb is used with a reflexive pronoun. (sometimes only the se pronoun is applicable, for other pronominal uses all of the reflexive pronouns (me, te, se, nos, os) are used.
That being said, Spanish uses these verbs in conjunction with a reflexive pronoun in a variety of constructions that changes or augments the meaning of the verb.
You will often hear these referred to a the passive se, the reflexive se, the impersonal se, passive-reflexive se, detransitizing se, etc., but keep in mind that some of these constructions employ all of the reflexive pronouns not just se, but some of them are limited to just the use of the se pronoun.
To try to explain to you what passive, reflexive, impersonal, detransitizing, etc. means would require too much space for a single answer, but just realize that the se pronoun is referring to a reflexive pronouns used in many different pronominal verb usages to say something differently than when the verb is used without the pronoun.
Se used as an indirect object pronoun to avoid 3rd person phonetic difficulties pales in comparison to its use as a reflexive pronoun, but realize that se can under certain conditions be an object pronoun.
It is all here at SpanishDict. see this lesson "3.12 - Se in Impersonal, Passive, and Unexpected Events". Also see the Referecne Section.
Se is that other thing that is doing something. El auto se vende. La casa se cayo. Again, that's only around here and that's how I hear it. That how I use it. I went and bought a new washer the other day because THE OTHER ONE SE roto. 
Got a dryer too, couldn't resist! It looked kinda stoooopid the one fancy front loader sitting next to an old top loader dryer. The OTHER NEW DRYER SE me llamo and I couldn't resist!
Se: forma del verbo saber(know) o del verbo ser(to be)
(yo) Sé que estabas alli = I Kwon that you were there. // (yo) se lo que quieres = I Know waht you want
Se un hombre. Be a man! // Se una buena persona = Be a good person
