Explain this code in C language:

//CLIENT PROGRAM:

int main(int argc, char *argv[]) {

struct sockaddr_in echoserver;

char buffer[255];

int sock;

sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);

memset(&echoserver, 0, sizeof(echoserver));

echoserver.sin_family = AF_INET;

echoserver.sin_addr.s_addr = inet_addr("127.0.0.1");

echoserver.sin_port = htons(atoi("6000"));

connect(sock, (struct sockaddr *) &echoserver, sizeof(echoserver));

printf("PLEASE ENTER TEXT: ");

fgets(buffer, 255, stdin);

write(sock, buffer, strlen(buffer) + 1);

printf("PLEASE ENTER TEXT: ");

fgets(buffer, 255, stdin);

write(sock, buffer, strlen(buffer) + 1);

printf("PLEASE ENTER TEXT: ");

fgets(buffer, 255, stdin);

write(sock, buffer, strlen(buffer) + 1);

close(sock);

exit(0);

}

//SERVER PROGRAM:

int main(int argc, char *argv[]) {

int serversock;

struct sockaddr_in echoserver;

unsigned int clientlen;

int clientsock;

struct sockaddr_in echoclient;

char buffer[255];

int result;

serversock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);

memset(&echoserver, 0, sizeof(echoserver));

echoserver.sin_family = AF_INET;

echoserver.sin_addr.s_addr = htonl(INADDR_ANY);

echoserver.sin_port = htons(atoi("6000"));

bind(serversock, (struct sockaddr *) &echoserver, sizeof(echoserver));

listen(serversock, 5);

clientlen = sizeof(echoclient);

clientsock = accept(serversock, (struct sockaddr *) &echoclient, &clientlen);

read(clientsock, &buffer[0], 255);

printf("Message from client: %s ", buffer);

read(clientsock, &buffer[0], 255);

printf("Message from client: %s ", buffer);

read(clientsock, &buffer[0], 255);

printf("Message from client: %s ", buffer);

close(clientsock);

close(serversock);

exit(0);

}