Command for vlookup function

[morning latte]

Hello experts,

I have large text files that need to be arranged using a function like excel's vlookup. I have been playing with awk command but didn't really come up with a solution. Could anyone please help me out? Below are my datasets and expected output. Any help would be greatly appreciated.

<File 1>
contig-100_1 5
contig-100_30 10
contig-100_50 20
contig-100_40 15
contig-100_60 25

<File 2>
contig-100_1 "Bacteria"
contig-100_50 "Bacteria A"
contig-100_60 "Bacteria A, Fungi B"

<Expected output>
contig-100_1 5 Bacteria
contig-100_30 10 NA
contig-100_50 20 Bacteria A
contig-100_40 15 NA
contig-100_60 25 Bacteria A, Fungi B

[lindenb]

you're looking for the 'join' command : http://linux.die.net/man/1/join