I'm old enough to remember when kids carried their books to school in either the briefcase-looking book bags a PP posted a picture of, or cloth sacklike things with drawstrings (the terms "book bag" and "school bag" were used interchangeably for these), or loose in their arms. In the third case, boys carried them in one arm hanging straight down, while girls held theirs horizontally at waist level, elbow bent. You risked teasing if you were a boy and carried your books "like a girl," or vice versa.
This was in elementary and junior high, when kids generally didn't have big stacks of books to take home each night. Homework was lighter (heck, in my district it was policy not to assign any homework until fourth grade!) and much of it could be done in study hall.
Carrying books in a backpack (we called them knapsacks) came into vogue when I was in high school.
I've seen bookstraps, which were rubber straps about an inch wide that you buckled around your books to hold them together on the trip to/from school, but they were passe by the time I came along. Never actually saw one in use.
Here's Baglady's bag breakdown:
Bag = Any soft-sided thing you carry stuff in
Sack = Shapeless cloth thing that Santa carries, and that potatoes and flour used to come in
Grocery bag = Paper bag without handles, or plastic bag with handles that you get your purchases packed in at the grocery store
Shopping bag = Paper bag with flat bottom and jute handles that you get your purchases packed in at upscale department or clothing stores.
Tote bag = Cloth bag with handles of the same material as the bag itself. If used for shopping, it's generally owned by the purchaser and presented at checkout for packing of purchases.
Pocketbook/Purse/Handbag = Soft-sided bag with handles generally carried by women and containing the stuff they need/use daily (money, makeup, phone, comb/brush, etc.). Can be made of leather, cloth, vinyl or other materials.
Change purse: Small pouch for coins only (although some people carry bills in it as well)
Wallet: Contains paper money, credit and other cards, and may also contain photos and other keepsakes. Women's wallets may also have a built in checkbook and/or change purse, and live in the pocketbook, if she is the pocketbook-carrying kind. Men's wallets, aka billfolds, do not have change purses and live in the hip pocket.
Clutch/clutch purse = Small handbag either without handle or with a wrist strap, used by women on formal occasions. Wildly impractical, if you ask me.
YMMV as always. I have had fun picking my own brain about these definitions!