flutter main vs cross axis

Column(
            // mainAxisAlignment: MainAxisAlignment.start, // column 전체에 대한 
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                room.name,
                style: const TextStyle(
                    fontSize: 40,
                    fontFamily: 'Geo-Reaular',
                    color: Colors.white),
              ),
              Text(
                'Tablet   0/5',
                style: const TextStyle(
                  fontSize: 20,
                ),
              ),
            ],
          ),

Column(
            mainAxisAlignment: MainAxisAlignment.start, // column 전체에 대한
            // crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(
                room.name,
                style: const TextStyle(
                    fontSize: 40,
                    fontFamily: 'Geo-Reaular',
                    color: Colors.white),
              ),
              Text(
                'Tablet   0/5',
                style: const TextStyle(
                  fontSize: 20,
                ),
              ),
            ],
          ),