What does hay mean in Spanish?

Hay is the impersonal form of haber and translates as 'there is' or 'there are'. It doesn't change for singular or plural - hay un coche (there's a car), hay tres coches (there are three cars). The past forms are había (there was / there were), hubo (there was - bounded event), habrá (there will be), habría (there would be) - all invariable for number. Hay is one of the highest-frequency verbs in Spanish and the standard way to assert existence.

What is the difference between es and hace for weather?

Spanish uses hace for most weather phenomena - hace frío (it's cold), hace calor (it's hot), hace sol (it's sunny), hace viento (it's windy). Literally 'it makes cold / heat / sun / wind'. Estar is used for adjectival descriptions - está nublado (it's cloudy), está soleado (it's sunny). Ser is rare in weather; you'll see it for general or repeated patterns - el clima es seco aquí (the climate is dry here). The default for talking about today's weather is hace + noun.

Spanish Impersonal Verbs

Some Spanish verbs and constructions don't take a personal subject. Things just exist, the weather just is, things just have to be done. These constructions are high-frequency and worth a dedicated page.

hay: existence

Hay is the impersonal present-tense form of haber. It translates as "there is" or "there are" and stays invariable regardless of whether the following noun is singular or plural.

Hay un coche en la calle. (There's a car in the street.)
Hay tres restaurantes aquí. (There are three restaurants here.)
No hay nadie en casa. (There's no one at home.)
¿Hay leche? (Is there any milk?)

It exists in every tense, all invariable:

Tense	Form	English
Present	hay	there is / are
Imperfect	había	there was / were
Preterite	hubo	there was (bounded)
Future	habrá	there will be
Conditional	habría	there would be
Present perfect	ha habido	there has / have been

The split between había and hubo mirrors the standard preterite-vs-imperfect rule: había tres personas for background description, hubo un accidente for a bounded event.

hay que: obligation

Hay que + infinitive expresses general or impersonal obligation - "one must" or "it's necessary to". No specific subject.

Hay que estudiar. (One must study.)
Hay que comer bien. (You have to eat well.)
Hay que pagar al final. (You have to pay at the end.)

For personal obligation ("I have to", "you have to"), use tener que + infinitive:

Tengo que estudiar. (I have to study.)
Tienes que pagar. (You have to pay.)

The two are distinct: hay que is generic and applies to everyone; tener que specifies who.

hace: weather and time

Hace comes from hacer (to make / to do) and serves two impersonal functions.

Weather:

Hace frío. (It's cold. - lit. it makes cold)
Hace calor. (It's hot.)
Hace sol. (It's sunny.)
Hace viento. (It's windy.)
Hace buen tiempo. (The weather's good.)
Hace mal tiempo. (The weather's bad.)

These all use hace + noun. The noun isn't an adjective - calor is heat, frío is cold. English would use an adjective ("it's cold"), Spanish uses a noun ("it makes cold").

Some weather uses estar with adjectives instead: está nublado (it's cloudy), está despejado (it's clear).

Time elapsed:

Hace dos años que vivo aquí. (I've lived here for two years. - lit. it makes two years that I live here)
Hace una hora que estudia. (He's been studying for an hour.)
Hace cinco minutos que llegué. (I arrived five minutes ago.)

The pattern is hace + time + que + verb. Spanish uses the present tense after que for an ongoing duration, and the preterite for a bounded past event.

se + 3rd person: the generic "one"

Spanish uses se + 3rd-person verb to make a generic, subject-less statement - the equivalent of English "one does X" or the passive "X is done".

Se habla español aquí. (Spanish is spoken here. / They speak Spanish here.)
Aquí se vive bien. (One lives well here.)
No se puede fumar. (Smoking isn't allowed. / One can't smoke.)
Se venden libros. (Books are sold. / They sell books.)

The verb agrees in number with the subject when one is present: se vende un coche (a car is sold - singular), se venden libros (books are sold - plural).

This is the standard impersonal in Spanish - more common than the passive voice (es vendido), which feels stiff in everyday use.

interesar / gustar / encantar

Verbs of liking and interest behave impersonally - the thing liked is the grammatical subject, and the person who likes it is the indirect object.

Me gusta el café. (I like coffee. - lit. coffee is pleasing to me)
Me gustan los libros. (I like books. - verb agrees with libros, plural)
Le interesa la política. (Politics interests him / her.)
Nos encanta esta canción. (We love this song.)

Verb agreement is with the thing liked, not the person who likes it. This catches every English speaker once. The cheatsheet covers the full pattern.

Worked examples

Hay mucha gente en la plaza. (There are a lot of people in the square.)
Hace mucho frío en invierno. (It's very cold in winter.)
Hay que ser puntual. (You have to be on time.)
Aquí se habla español y catalán. (Spanish and Catalan are spoken here.)
Hace dos meses que estudio chino. (I've been studying Chinese for two months.)
No me gusta el café. (I don't like coffee.)
Hubo un accidente anoche. (There was an accident last night.)

Common mistakes English speakers make

Pluralising hay: hayn doesn't exist - it's always hay for both singular and plural. Confusing hay (there is) with es (it is): hay un problema (there's a problem), not "es un problema" unless you're identifying a specific known thing. Using está for weather where Spanish wants hace: está frío is wrong for "it's cold"; it's hace frío. And forgetting the agreement on gustar: me gusta los libros is wrong, it's me gustan los libros.