UnderStanding Asynchronous Code, and API's
2021-8-16 Less than 1 minute
# UnderStanding Asynchronous Code, and API's
1. What is the difference between asynchronous code and synchronous code?
Synchronous means you can execute only one thing at a time. Asynchronouse means you can execute multiple thinks at a time.
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2. What is an event listener?
A procedure that waits for an event to occur.
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3. What does the O represent in the SOLID principles?
Open-closed Principle. Objects should be open for extension, but closed for modification.
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4. What is a callback / higher order function?
A function passed into another function as an argument, which is then invoked inside the outer function to complete some kind of action.
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5. What is a promise? How do you capture an error from a promise?
A process that is already happening. you use catch() to capture an error.
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6. Name three processes used to make requests over HTTP?
GET
POST
PUT
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7. What does the API acronym stand for?
Application Programming Interface
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8. In the MVC design pattern, who is responsible for making calls to APIs?
The Controller
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9. What is the purpose of encapsulation in programming?
To make non-public parts of a code non-public.
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10. What is HTTP response code for a successful request?
200 series
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11. What is a 500 error?
Internal Server Error
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