Learn English – Which spelling is correct? Theatre or Theater

"Visualization" is the only correct spelling in American English.

"Visualisation" and "visualization" are both acceptable in British English although it is a common misconception that "visualization" is an Americanism and therefore incorrect.

Oxford resolutely prefers "ize" forms - see visualize in the British English Oxford Dictionary - and a lot of academic writing follows their lead but most mass market publications prefer "ise".

There's more information in Wikipedia and an interesting article with further references.

You have four examples due to how the words are being used differently in each case.

The noun phrase “brute force” describes the raw strength used to achieve or get through something. For example: "Greg used brute force to open the stuck door."

Below is an explanation of the different formats you found. I have also linked to an article about hyphens and why they are used sometimes and not other times.

• brute-force: This is “brute force” used as a compound modifier (similar to an adjective), so it is hyphenated to keep it as a single modifying phrase.

• Brute Force: This is a title of a product and is written with title case for that reason.

• bruteforce: This is again the name of a product, that the trademark holders have chosen to spell as one word.

Hyphens have many uses but in this case the focus is on how they are used with Compound Adjectives. When multiple Adjectives come directly before a noun they are known as compound modifiers and they can be hyphenated. They do not have to be hyphenated however as you can see in the first two examples you provided being technically correct either way.

A more in-depth explanation as to when to and not to use hyphens can be found here