Whenever you copy-paste anything from other webpages, PDF or from Word Pad etc to Visual Editor of WordPress, it automatically copies the formatting like text color, style, type, size etc and hence for avoiding this bloggers mostly paste the text in WordPress text editor instead of visual editor but then also sometimes you make things difficult, For Example: Suppose you want to copy paste a big amount of text (including all content links) from a website: Then in that case if you copy paste the content to visual editor, it will put all useless formatting works which certainly be looking odd on your website OR if you paste it to HTML text editor then it will not copy the content formatting and style but your links will also be removed and then you will be having to add links one by one.
Now what should be done to make this job easy and quick. WordPress already provides you a very easy solution, it is a default feature of WordPress and there is no need of installing any new plugin or adding any hack to your functions file.
Very few website owners notices, there is a small TinyMCE button present in the (second row’s 7th button) of default visual editor of WordPress with tooltip ‘Remove Formatting‘. All you need to do is paste the copied text in visual editor, then select the text and click this ‘Remove Formatting‘ button and the formtatting will get removed leaving your links safe.