B

bakeClip
bakeFluidShading 
bakePartialHistory
bakeResults
bakeSimulation
basename 
basenameEx 
baseTemplate
baseView
batchRender
bessel
bevel
bevelPlus
bezierAnchorPreset
bezierAnchorState
bezierCurveToNurbs
bezierInfo
bindSkin
binMembership
blend2
blendShape
blendShapeEditor
blendShapePanel
blendTwoAttr
blindDataType
boneLattice
boundary
boxDollyCtx
boxZoomCtx
bufferCurve
buildBookmarkMenu
buildKeyframeMenu
button
buttonManip

indicates a MEL script