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What is Execution Time?
-Use correct data types
-Avoid gratuitous use of global variables
-Declare variables at the top of their scope
-Use a single var statement
-Use === instead of ==
– don’t eval()
-Use techniques to reduce number of function calls
Use an object pool to recycle objects
-Implement memoization for speedier execution of recursive functions
-Minimize number of DOM elements
Minimizing External HTTP Requests
There are a couple of ways to reduce the number of HTTP requests:
1) Use a CDN: Content Delivery Networks (CDNs) host your files on multiple servers around the world. When a user visits your website, they will be able to download your files from the server that is closest to them, which will reduce the amount of time it takes for the files to transfer.