User Names and White-Spaces

user-input account
VarunGupta picture VarunGupta · Oct 16, 2008 · Viewed 16.2k times · Source

In past many years I have registered on various applications and platforms hosted online or offline.

Why white-spaces are not allowed in User Names as spaces are very natural to names and most of the computing systems can handle them efficiently.

(Many people can raise similar questions about other special characters which are illegal. But their case is far more understandable as they are not even natural to real world naming schemes. And surely!)

Answer

Martin Liversage picture Martin Liversage · Dec 14, 2009

One subtle problem related to spaces in user names is that the space character is "invisible" and two consecutive spaces may look very similar to a single space. Errors that arise from entering two instead of one space can be hard to spot and this is one reason to disallow spaces all together.

Some systems may disallow spaces but still allow a non-breaking space. A smart user can use this fact to include a space in his user name.

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