Answer: worked in a Histology Lab for 38 years. Histology is the microscopic study of tissue’s appearance, organization & function.
The four main types of human tissue are epithelial, connective, muscle & nervous.
As for as similarities,
Each of the 4 tissue types are made up of specialized cells that are grouped together according to structure and function.
Every cell in each tissue type is made up of 13 parts, one of which is the nucleus.
Every nucleus is made up of 4 parts.
I am assuming you are asking about only human tissue. If you are including plant tissue, the answer would be differe