Insha'Allah

Insha'Allah translates to "God willing" but has a wide variety of meanings across the Islamic world.

In some areas of the world/contexts it just means "Hopefully," as in:
"Are you going to make it to dinner tonight?"
"Insha'Allah"


In some areas of the world it means "No," as in:
"Will we have a break?"
"Insha'Allah!"

In some contexts it means "I don't want to answer this question," as in:
"Mom, can we go get candy today?"
"Insha'Allah!"
(This is the equivalent of an American parent telling their child "Yes" as a way of avoiding the issue and then realizing 4 hours later that, as a result of thoughtless "yes"'s, the child is now owed candy, ice cream, and cookies. Insha'Allah is better! Bet you wish you knew this one when Natalie was a child, right mom?)


And lastly it means literally "If God wills it". From the wiki: 
One's use of Insha Allāh indicates not one's desire to succeed in an endeavor, but rather that the endeavor one embarks on will be within God's will, which might be interpreted as that which is best for Humanity, the Earth, and all of Allah's creation. It indicates one's desire for being in tune with God's plan... It is commonly used by Muslims, but is also common in Christian groups in the Middle East, like the Coptic Orthodox Church... The phrase also acknowledges submission to God, with the speaker putting him or herself into God's hands, and accepting the fact that God sometimes works in unexpected ways.

In the Qu'ran, Muslims are told that they should never say they will do a particular thing in the future without adding "in sha'Allah" to the statement.^[1] ... Surat Al Kahf (18):24: "And never say of anything, 'I shall do such and such thing tomorrow. Except (with the saying): 'If God wills!' And remember your Lord when you forget...'"

In other words, whenever you talk about the future, you have to say "Insha'Allah" because it indicates your desire to submit to God's will, a generally central theme of Islam (which means "submission" and a Muslim is "one who submits")

As an example of its usage, something that's happened to me a few times is I get into a cab, say something like "safarat miSr 3fak?" = "The Egyptian embassy please?" (it's the most well-known place near school, and the 3 is pronounced like you're gagging) and the cab driver responds:
"safarat miSr? Insha'Allah!"

This is a really common occurrence and I still find it funny because I really just want him to say "OK," not "hope so!". But I take what I get I suppose.