What makes space and quote characters "unsafe?"

What causes certain characters to be "unsafe"?

What is it about the spaces and quotes here
var example = "\"Quoted Value with spaces and &\"";

which makes them unsafe?

After encoding the encoded that string, it becomes: %22Quoted%20Value%20with%20spaces%20and%20%26%22.

newbiewebSr. Software EngineerAsked:
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Shaun KlineLead Software EngineerCommented:
For URL encoding, passing an ampersand (&) in the URL would cause issues, as it is used to separate name/value pairs in a query string. Spaces are encoded because some older web servers could not handle them correctly because it broke up the URL into pieces. Many Unicode characters are also encoded because many US/English based web servers can only handle single byte characters.

HTML encoding has similar issues, such as the less than sign (<). If that was included in a URL and then displayed on a page, it could cause the HTML to break.

It all depends why the encoding occurs.

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