memory usage....help....

[JSeverino@etek.cl]

Hi:
Mem  "used" is more big ?
Mem "free" is more little ?
whats......???

thanks.....no speaken english....sorry

  2:05pm  up  2:39,  1 user,  load average: 0.00, 0.00, 0.00
55 processes: 54 sleeping, 1 running, 0 zombie, 0 stopped
CPU states:  0.1% user,  1.7% system,  0.0% nice, 98.0% idle

Mem:   257744K av,  254608K used,    3136K free,   19252K shrd,  208584K buff

Swap:  530104K av,       0K used,  530104K free                   14764K cached

  PID USER     PRI  NI  SIZE  RSS SHARE STAT  LIB %CPU %MEM   TIME COMMAND
 1307 root       4   0   552  552   452 S       0  1.1  0.2   0:03 syslogd
 1545 root      15   0   860  860   668 R       0  0.7  0.3   0:04 top
    1 root       0   0   380  380   308 S       0  0.0  0.1   0:37 init
    2 root       0   0     0    0     0 SW      0  0.0  0.0   0:00 kflushd
    3 root       0   0     0    0     0 SW      0  0.0  0.0   0:00 kupdate
    4 root       0   0     0    0     0 SW      0  0.0  0.0   0:00 kpiod
    5 root       0   0     0    0     0 SW      0  0.0  0.0   0:00 kswapd
    6 root     -20 -20     0    0     0 SW<     0  0.0  0.0   0:00 mdrecoveryd
  462 root       0   0   620  620   512 S       0  0.0  0.2   0:00 crond
  476 root       0   0   488  488   416 S       0  0.0  0.1   0:00 inetd
  485 named      0   0  1712 1712   924 S       0  0.0  0.6   0:00 named
  487 named      0   0  1708 1708   920 S       0  0.0  0.6   0:00 named
  561 root       0   0   652  652   436 S       0  0.0  0.2   0:00 rinetd