k is good for data and analytic servers. k runs on LINUX, NT and UNIX. design goal: speed write fast, run fast, modify fast. minimize product of vocabulary and program size. examples: [java, vb and c++ require 4 to 400 times as much code.] 1. "hello world" 2. maximum subsequence sum, cf. "programming pearls", jon bentley f:|/0(0|+)\ / max OVER 0 init (0 max plus)SCAN f 2 1 -4 2 -1 5 3. spreadsheet, cf. http://java.sun.com/applets/SpreadSheet S..t:"S[.;`f]:.[`D;(;);{. y};S[]][]" / trigger: re-evaluate S:D:.+(`a`b`c`d;4 5#,"");`show$`S / initialize and show the eight hundred and forty lines of java code do less. 4. BDT, cf. "one factor option model ..." Black, Derman, Toy bdt:{[p;v] bn:{.5*+':0,x,0} / binomial step function l:(-1+%%':p)*_exp v*(2*!:'x+1)-x:1_!#p / generate approximate lattice l:{x:bn x;x%1+y*(+/x%1+y*)?z}\[,*p;l;1_ p] / fit wtd-discount exactly (*l){x%bn y}':l} / wtd-disc to forward bdt[*\3#%1.1;.1] sixty sixty-period arbitrage-free lattices per second. (200MHZ pentium) 5. simple web-server(k -h 80) .m.h:{\x;"hello world"} / display message x http://localhost applications are written faster and run faster. the more complex the application the greater the gain.