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Open a text editor "Notepad" and copy the following entry:
Here is an invisible symbol)))
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In this example, the symbol acts as an invisible hyphen.You can use other characters or words.
save a text document on your computer.
Load the document to ftp-server of your domain.
Open the resulting page.Instead, you will see a dash empty string.Now select and copy an entire page in the "Notepad", the hyphen will again become visible.
Copy hyphen or your invisible characters from the "Notepad" in the field for entering the nickname or message.
You can use already prepared a null character.Click on the link and also copy the page
in the "Notepad".
Check works or not your invisible character you can now, for example, the site "VKontakte".For this field to enter a comment, copy the invisible character from the "Notepad", and now send your message.It must be empty.Now try to send an empty comment, without the addition of a symbol.You will not succeed.
Very often an empty nick in chat on the forum, the guest book is created to communicate without restrictions.Remove or block this user is impossible, so it is able to violate with impunity the rules in force on the site, such as sending spam or insult other users.Of course, empty symbols are used in good order.For example, such a trick is often used by webmasters when you do not know how to do just a lot of padding in a html-code of your page.Also invisible nickname may be useful if you want to make fun of your friends in ICQ.Using the above method, you can write invisible messages.