Guttation is the loss of water from leaves in the form of liquid which is not pure water, it contains minerals with organic compounds like hormones, vitamins proteins etc., and this water is called gutteted water. Natural guttation can be observed in the early morning or late hours of the day.
Guttation occurs due to positive root pressure. Water releases from the opening called hydathodes, it is also known as water stomata or water pore, this pores always remain open.
Transpiration is the loss of water occurs from the aerial part of the plant in the form of vapors, is called transpiration. The vapor is a pure form of water. Transpiration occurs due to negative hydrostatic pressure generated by transpiration pull.