What is assembler programming language like?

Assembly languages vary by the intended architecture.

In general, assembly languages are very basic when compared to higher level languages like C, Java, Perl or Python, consisting of only a few dozen instructions. These instructions are grouped together to form higher level operations. Generally, it takes many lines of assembly code to do the same task as a few lines of higher level code.

Variables are not 'named' like in high level languages and are limited in quantity. However, greater control over storage locations can be acheived. For instance, r0 would refer to a variable stored in register 0. Mathematic operations are often performed by logical operations (AND, OR, XOR etc etc).