DES and AES are quite different from each other, although both are symmetric block cyphers.

Differences between DES (Data Encryption Standard) and AES (Advanced Encryption Standard) 

DES (Data Encryption Standard)

DES was first adopted by National Institute of Standard and Technology in 1977. In DES for encryption of data, it needs to be dividing into two halves before it is processed through DES algorithm. The structure of the DES encryption is basically based on Feistel Cipher structure (where the plaintext divides into two halves L (left) and R (right) and then pass through the substitution and permutation processes).

The plaintext for encryption needs to be of 64 bits. The key size of DES is smaller than that of AES. The numbers of rounds that the plaintext needs to be processed before transmission are 16. These rounds include the processes like Xor, S-box (substitution box), P-box (permutation box), Expansion Permutation, Xor and swapping. The smaller key size of DES also makes it quite insecure. The speed of DES is also slow than AES.

AES (Advanced Encryption Standard) 

AES was first published by the National Institute of Standards and Technology in 2001. AES takes the entire plaintext as an input for processing. AES is not based on a Feistel structure, but it is based on the Substitution and Permutation Principle.

The plaintext that AES takes as input should be of 128,192, or 256 bits. AES uses a larger key for encryption and decryption as compare to DES. The rounds for processing of data used by AES is based on the algorithm used at a time, such as for 128 bits algorithm there are 10 rounds, for 192 bits algorithm there are 12 rounds, and for 256 bits algorithm there are 14 rounds. The rounds in AES include processes like Subbytes, Mix columns, Shiftrows, and Addroundkeys. As the size of the key is larger than DES, so it is more secure than DES. It is also faster compared to the DES algorithm.