In this YouTube video on Class4crypt c4c10.6a Cifrado y descifrado con RSA (parte 1), the speaker discusses the RSA algorithm, its encryption and decryption processes, and its application for digital signatures. Prime numbers are chosen, multiplied to obtain the modulo, and a public key is established that satisfies the multiplicative inverses condition. Private keys can be computed using the extended Euclidean algorithm or the Carmichael function. The algorithm is slow compared to symmetric cryptography, making it primarily used in educational or laboratory settings or for encrypting small secret numbers. The next video will explore how to apply encryption and digital signatures simultaneously using RSA.