Aigiri Nandini Stotram was composed by Adi Shankaracharya. It was popularized in middle ages by Ramakrishna a devotee of Mahakali and courtier of Raja Krishna Devarayaa. Ramakrishna is more popularly known as Tenali Rama.
The meanjng of this stotra can bd found jn this link
https://shlokam.org/ayigirinandini/
Mahishasura Mardini Stotram is said to bring peace to the devotee and removes all fear and sadness. It drives away negative emotions like doubt, anger, ego and inertia. This stotram also removes obstacles from the path of the believer.