Inserting © (copyright symbol) using Microsoft Word

Assuming you have auto-correct enabled, type (+c+)

Also works with (+r+) for the Registered symbol, and (+t+) for the Trademarked symbol [shout out to dissemin8or].

Note: The above are case insensitive.

On Windows: Press Ctrl + Alt + C to insert © (copyright symbol).

Tested with MS Word 2016.

As commented by @Richard:

Another way is to hold down Alt and type numpad digits 0169, then release Alt button. This work anywhere not only in MS Word.

On Windows 10, regardless of what application is running, you can bring up an "emoji keyboard" which also contains many useful symbols:

Hold down the Windows/flag key, and press the . or ; key.

The window that pops up is split into three main sections along the top:

• Graphical emojis (marked 🙂)
• Text-based emoticons/smileys/kaomoji (marked ;-)
• Punctuation and symbols (marked Ω)

Each of those three sections has sub-sections selected along the bottom.

To get to "©":

• Select the section labelled Ω ("Symbols" if you hover over it) at the top
• Select the sub-section labelled < ("General punctuation" if you hover over it) at the bottom

Once you use it (or any other symbol) once, it will appear on the sub-section marked with a clock, which is your recently used items.

Posting this in addition to the other great answers, since it works for any symbol:

On the ribbon, "Insert" > "Symbol" > "Copyright Sign" (see "Special Characters" tab for Shortcut keys)

https://support.microsoft.com/en-us/office/insert-a-symbol-in-word-2a061ae9-5a6c-4407-b618-8dc3c9fd4f44

Just to add another method in Windows not mentioned in other answers, you can use the Character Map app:

Start > Windows Accessories > Character Map

or from the Run prompt:

WinKey + R > charmap

It contains all the characters for all the installed fonts in a GUI app that you can select, copy to the clipboard and paste anywhere in Windows that accepts text. It also displays the ASCII keystroke code if available for a particular character (Alt+0169 for © as mentioned in @ComradeChe 's answer).

More information from Microsoft Support.