Depending on the type of decision being made, resolutions are considered ordinary or special. Both types can be passed in a meeting or by circulating written resolutions, assuming a company's governing documents do not prohibit using circulating resolutions for some or all decisions.
Ordinary resolutions refer to decisions regarding daily operations. Generally, to pass an ordinary resolution at a meeting, over 50% of a company's shareholders need to vote in favour. However, to pass an ordinary resolution by circulating a written document instead of holding a meeting, all shareholders must unanimously sign it.
Special resolutions are used for more important decisions. Special resolutions require more than a simple majority. Often, shareholders with at least 75% of the company's shares may need to vote in favour to pass a special resolution at a meeting. The required majority can be higher than 75% depending on the terms of the company constitution. However, to pass a special resolution by circulating a written document instead of holding a meeting, all shareholders must unanimously sign it.