the data rate
If a signal is a conveyor belt and the bits are boxes riding it, the data rate is simply how many boxes per second roll past you. It is measured in bits per second (bps), and its bigger cousins kbps, Mbps, and Gbps — a kilobit is 1,000 bits, a megabit 1,000,000, a gigabit 1,000,000,000. A '100 Mbps' link can move one hundred million bits every second.
Precisely, the data rate (or bit rate) is the number of information bits the physical layer pushes onto the medium per second. It is not the same as a link's bandwidth, which is a range of frequencies measured in hertz (Hz) — the physical 'width' of the channel. Bandwidth is the road; data rate is how many bits you actually drive down it per second. A wider channel and a cleaner channel both let you raise the data rate, but the relationship is set by hard physics: Nyquist's formula for a clean channel and Shannon's capacity for a noisy one give the ceiling no clever engineering can beat.
Watch the units carefully. Network speeds are in bits per second (lowercase b), while file sizes are usually in bytes (uppercase B), and one byte is eight bits — so a 100 Mbps link downloads at best about 12.5 megabytes per second, not 100. And data rate is capacity, not delay: a fat 1 Gbps link can still feel slow if latency is high, because rate is about how many bits per second, while latency is about how long each bit takes to arrive.
Your plan says 'up to 1 Gbps'. Downloading a 1.5-gigabyte (= 12 gigabit) file at a sustained 1 Gbps takes at least 12 seconds — and that is bytes-to-bits arithmetic, before any real-world overhead and latency.
Data rate is capacity in bits/second; divide by 8 to compare with byte-sized files.
Data rate is not throughput. The advertised data rate is the link's capacity; throughput is the rate you actually achieve, which protocol overhead, congestion, and a slow far end can drag well below it.