Culture(s) / Postcard writing conventions

A1 Breakthrough
In your country, in your culture, do you write postcards? Do you always send a postcard when you're on holiday away from home? Who do you send a postcard to? To an older family member, to friends, to neighbours? Can you send a card to say thank you? What are the postcard writing conventions in your culture?
 
In French-speaking countries, there are a few classic elements that are more or less always used, as you can see in Émilie's postcard to TV5MONDE.

1. Date: the day, the month (spelled out), the year.
2. Greeting: "Chers amis, Chère maman, Chers vous tous, Salut (Sophie)" [Dear friends, Dear mother, Dear you all, Hi (Sophie)], always followed by a comma or possibly an exclamation mark for "Salut".
3. You specify the place where you are: "Nous sommes en vacances dans un endroit de rêve, au bord de la mer, on se repose à la campagne, je suis aux sports d’hiver dans les Grisons, etc." [We are on vacation in a dream place, by the sea, resting in the countryside, I am skiing in the Grisons, etc.]
4. You say how you are (physical fitness and/or mood): " Je vais très bien, nous sommes en pleine forme, cela fait beaucoup de bien, on s’ennuie, etc." [I'm fine, we're in great shape, it feels very good, we're bored, etc.]
5. You write about what you're doing / you did, you let people know about your usual schedule while on holiday: " On lit, on se promène, on se baigne tout le temps, la gastronomie locale est formidable, etc." [We read, we go for walks, we go swimming all the time, the local cuisine is amazing, etc.]
6. You talk about the weather: "Il fait beau, chaud, un temps splendide, épouvantable, il pleut, le ciel est toujours bleu, etc." [The weather is nice, it's warm, beautiful weather, terrible weather, it's raining, the sky is always blue, etc.]
7. Announcing when you're coming back: "À bientôt, on rentre le 10, on se retrouve à la fête de Tante Henriette, à plus, etc." [See you soon, we'll be back on the 10th, we'll meet at Aunt Henriette's party, see you later, etc.]
8. Personal closing line: "Affectueusement, tendrement, je t’embrasse bien fort, bises, bisous, etc." [Affectionately, tenderly, lots of love, hugs and kisses, etc."]
9. Signature: First name