"Hunden är glad."

Translation: The dog is happy.

[RodolfoJonasson]

Of course, the DL's dog eats the cat many times ...

[Gin1]

so "Glad" and "Lycklig" both mean happy
are they interchangeable ?

[Arnauti]

They represent different feelings.
glad is a more short-term happiness, like merry. You're likely to laugh when you're glad.
lycklig is a bigger feeling, more to do with fulfillment.

In some expressions, only one of them works.

[BobShmob]

In addition to what Arnauti said, something for speakers/learners of german:

"glad" and "lycklig" are "fröhlich" and "glücklich", I believe.

Notice that english "glad" is "froh" in german. Also, "färgglad"="farbenfroh".

[Uppsala18]

In Dutch: glad=blij and lycklig=gelukkig (?)

[Matt92HUN]

Does glad not mean glad?

[Lundgren8]

It’s usually better translated with ’happy’, but it can correspond to English ’glad’ as well.

[Matt92HUN]

Just because it didn't accept glad.

[devalanteriel]

Added it now. :)

[Matt92HUN]

Nice.