Panel  - adds a separate panel or paragraph to the presentation of your survey that can be controlled and made visible or not dependent on answers to previous questions.

Please refer to the article Survey Designer - Question Editor

Matrix (single choice)  -  adds question format that allows for a single choice from a matrix presentation of answer to a single question.  

Please refer to the article Survey Designer - Question Editor

Matrix (multiple choice)  -  adds a question format that allows for multiple answers from a matrix presentation of pre loaded answers for a single question. The columns format can be chosen from the selection of question types in the General tab such as drop down lists, radio-groups, text etc.

Please refer to the article Survey Designer - Question Editor