Today, logo is identity of company & secret of great business. People recognize you by your graphic identity, it is reflected by your company name, logo, business card, website, app etc.
Logo detail is depend on your nature of business or your own choice.
How many types of logo?
Lettermarks: HBO, NASA, IBM Only name is enough.
Wordmark: Coca-Cola, Google, Visa, Great Typography or define your business Google logo is great example of this.
Pictorial: Apple, Twitter, Puma, Android, Based on your logo text that define easily & have strong identity in viewer’s mind.
Abstract: Pepsi, BP, Adidas, Nike Swoosh, Rebook, It’s based on geometry my vision 2 design logo also a geometrical lines + abstract shape.
Mascots: KFC, michelin tyre, Mickey Mouse, Coco Monkey, Poppin’ Fresh by Pillsbury, amul girl, Duracell bunny, Air india maharaja
Combination: Burger King, Lacoste, starbucks
My experience, always choose a clear logo that can define your goal in your target market. If mostly people easily understand your concept, name, brand, words in your logo, then you are a winner.