How much memory do I have?

Red Hat

# cat /proc/meminfo | grep MemTotal

MemTotal:        5855444 kB

# free
             total       used       free     shared    buffers     cached
Mem:       4085896    3409048     676848          0     242128    1681144
-/+ buffers/cache:    1485776    2600120
Swap:      6193144      37164    6155980