Here is a list of terms and abbreviations commonly used in crochet. These are US terms, which slightly vary from UK terms. Always double check which terminology is being used to avoid your pattern turning out differently than expected!
ch
slst
st knot
mr
sc
hdc
dc
tc
inc
dec
cont
FL
BL
FP
BP
rep
rnd
sp
st
chain
slip stitch
slip knot
magic ring
single crochet
half double crochet
double crochet
triple crochet
increase
decrease
continue(d)
front loop
back loop
front post
back post
repeat
round
space
stich